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When to test for HIV during and after completion of PEP

I get this question a lot.

First of all, data on this is lacking and very hard to come by.

There are many theories that hypothesize that PEP reduces viral replication and delays sero-conversion and therefore make HIV testing less accurate. These theories have neither been proven nor debunked.

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Furthermore, there is very limited data on the use of P24 antigen tests (including Combo/Duo tests) and viral load testing for diagnostic purposes in patient who have or undergoing PEP. In fact, studies on monkeys (and more limited studies on humans) have shown positive viral load tests in individuals who were subsequently found not to be infected. This could represent an aborted infection (which is what PEP is supposed to and designed to do) rather than a true false positive. This illustrates one of the limitations of using viral load tests to diagnose people currently on or have completed PEP.

Official Guidelines

The US CDC Guidelines on Antiretroviral Postexposure Prophylaxis After Sexual, Injection-Drug Use, or Other Nonoccupational Exposure to HIV in the United States recommends that patients should be tested for the presence of HIV antibodies at baseline, 4 – 6 weeks, 3 months and 6 months post exposure.

The Joint WHO/ILO guidelines on post-exposure prophylaxis (PEP) to prevent HIV infection recommends HIV testing at baseline, immediately after completing PEP (i.e. 4 to 6 weeks post exposure) and again ‘3 – 6 months post exposure’.

The 2 guidelines are rather similar although the US CDC seems to be more firm on the requirement of a test at 6 months compared to the WHO guidelines.

Very recently, the New York State Department of Health AIDS Institute’s adult HIV guidelines committee undertook a comprehensive re-evaluation of its HIV occupational PEP guidelines and issued some changes which included shortening of the time of HIV testing after exposure to 3 months if modern, blood based, standard HIV testing is performed. This is certainly promising however it refers to occupational HIV exposure only and the same data and recommendation may not be extended to non-occupational exposure.

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 In short, most official guidelines still recommend testing at 6 months for patients who have undergone PEP.

Sometimes testing at 3 months post exposure is good enough but this really depends on what kind of test is done.

My own experience is the test done at 4 weeks exposure (or immediately upon completion of the PEP medications) is very indicative. I will still recommend a retest at 3 months although I have yet to see the test at 4 weeks get it wrong.

At the end of the day, the best person to advise you is still the doctor who prescribed you the PEP. He/She will be most familiar with the sensitivity of local tests available and the local guidelines.

If you have any questions, visit our free online forum on sexual health, HIV and STDs.

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About Dr. Tan
Dr. Tan graduated from the National University of Singapore in 2001. His residency was in the two largest public hospitals in Singapore; Tan Tock Seng Hospital and Singapore General Hospital.

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  1. Hello Dr Tan
    I am a male heterosexual. I had insertive vaginal sex with a sex worker here in Switzerland. Unfortunately, the condom broke. I had come in her. I withdrew then realised what had happened. I do not know status of female.
    I went to the hospital and received pep consisting of kaletra and combivir. I took my first tablets after 5 hours – quite fast. I am on my 6th day of treatment. No missed doses and I do not intend to miss any! I will do the usual 28 days.
    After reading your previous posts I see you are critical of these medications. Why? Solely their side effects or also their effectiveness?
    I feel rough but if things don’t get worse I can tolerate it.
    Is it really sensible to have an hiv test right at the end of pep? If negative what level of confidence should that provide?

    • Both side effects as well as effectiveness. The side effects of Zidovudine is certainly well studied and because of that, it is no longer recommended as PEP by some guidelines. From personal experience, I find the side effects of Kaletra very intolerable for my patients compared with the newer drugs we have. As for efficacy, there is not a whole lot of good solid data on that. But what we have seems to point to the fact that the new regimes are better. Also from personal experience, I have seen the old regime fail and not the new. According to guidelines, the first follow up HIV test should be within 2 weeks of completing the PEP. I think this makes a lot of sense. The accuracy of this test really is close to 100%.

  2. Hello Dr,
    I took PEP for 30 days, after they initially gave me pills for 3 days they gave me the rest of the meds in unopened packages. I took the pills (Combivir and Kaletra) for 30 days but I still have pills for 3 more days. The doctor said to take them as well. What should I do? Will it make any difference if I take PEP for a total of 33 days? Also could the virus hide in the mucous membranes and resurface after PEP, given that the exposure was sexual? Is that possible? I have experienced some rash on my penis and maybe that is why I am paranoid. Could that be from the exposure to HIV?
    Thank you in advance

    • I honestly do not think taking PEP for an extra 3 days is going to make much difference. The HIV virus cannot hide in the mucous membrane. There are too many things in there that can kill it.

  3. Hello Dr. Tan,

    I took PEP for 29 days and tested(ECLIA 3gen/ 4gen I am not sure) at day 64th (35 day post PEP) I know it is not conclusive but how reliable is the test ?

    Thank you Dr.

    • Extremely reliable. As good as 100%.

      • I mean how accurate is the test. Do you think my result will be/ won’t be likely to change at 12 week?

        Thank you very much for your work. Your website is very formative.

  4. Hi Dr. Tan,
    I’ve been reading your website a lot everyday, since I had a high risk sexual exposure and started taking PEP. I’m 20 years old and I had unprotected receptive anal sex for less than 1 minute (though we were having protected sex after that and it was irritating, it was kind of an accident) with a guy who was later confirmed to be HIV+ and who had Syphilis as well. He did not know about his status, so maybe his VL can be high or moderate. Another bad factor is that I had HPV and had done a surgery there in November. The guy said he did not ejaculate, but there could have been pre cum involved anyway.
    So I started taking PEP 40 hours after the exposure. On a regimen of Combivir and Kaletra (I have read what you said about this regimen, but I was given no choice). Fortunately the side effects are very mild and I’m able to keep it with 100% adherence.
    I am going paranoid while waiting until I can test. I keep getting doubts about the PEP’s efficacy. The infectologist that I talked to said he had personally never seen a PEP failure.
    1) Do you think that taking the PEP 40 hours after the exposure was still a good timing?
    2) I know it’s impossible to give accurate odds on this, but do you think that I have good chances of not seroconverting if I take my PEP with 100% adherence?
    Thank you a lot!

    • Which infectologist did you see? 1. PEP is recommended to be taken within 72 hours of exposure. Preferably within 48 hours. So 40 hours is OK. 2. The PEP regime you are on is about 80% to 90% effective. That is assuming you caught HIV. Given that you had unprotected receptive anal sex with a HIV +ve person not on treatment, I would say your risk is really significant.

      • Thanks for the answer, Dr. Tan.
        It was the infectologist who will test me after I complete the PEP here in Brazil.
        So the efficacy would be about 80-90% if I caught the virus. I understand that my risk was significant. I just it works well.
        Do you think I can be more optimistic? I keep getting paranoid about things like imagining the guy can have a high viral load.
        Another question, do you think that heat can affect the meds?

        • I mean, I just hope it works well.

        • Kaletra has to kept in the fridge unless it is the meltrex formulation then it should be kept under 25 degrees celsius like any other medicine.

  5. Hello Dr. Tan,

    When you mention that you have yet to see a 4 week test go on to subsequently test positive at 3 months. Are you referring to both 3rd and 4th generation tests?

    • 4th Generation tests.

      • Thank you for your quick reply, Dr. Tan. One more question. In your opinion would you say that a 4 week post exposure (Negative), 3rd generation test is a good indication of my HIV status? Just asking, since I know the CDC states that antibodies are detected between 2-8 weeks.

        Thanks for your time and information, in advance.

        • Yes, in fact a very good indication.

          • Thank you so much. You provide an invaluable service for those like myself who are in need of quick and accessible information from experts like yourself. You have made my day with your response. Although, I understand I must test in 3 months for a conclusive HIV test.

  6. Hello dr tan
    I just got my 28 day post exposure test as non reactive …. (On truvada as pep)
    So now i have my 14 and 28 day post exposure result as non reactive
    Can i relax … Are these tests indicative and should i be relieved and move on in my life or there are still chances of seroconverting in future …
    What do you think about my situation ..
    Also i had no ars symptoms till date

    Dr tan through your site you are doing a very generous job and my god bless you with sucess and all the luck in life

    • Dr waiting for your reply…very anxious

    • As I said in the article above, my personal experience is that the HIV test done immediately upon completion on PEP is already very accurate. I have personally not seen that test get it wrong. However, all guidelines recommend a retest at 3 months and you certainly should do that. Although most likely your test at 3 months will be fine.

      • Thank you very much doctor may you achieve all sucess in the world..

        • Hello dr
          Today i got another combo test done ie
          14 days post exposure — non reactive 0.13
          28 days post exposure — non reactive 0.11
          42 days post exposure — non reactive 0.9
          Took pep ( truvada alone ) for 29 days
          Should i consider test at 42 day conclusive or still need to test at 12 weeks post exposure …,? What do you suggest about my condition ..

  7. Hi Dr Tan
    I took Combivir about 60hrs after a possible exposure. I stopped taking the PEP 8 or 9 days later after feeling very ill. I took a 4th generation ELISA test 21 days later which came back negative and then another 4th gen ELISA Duo test at 32 days which also came back negative. I’m not sure if the first test was a duo but the 2nd definitely was. I had a white furry tongue which was present when I took both tests.
    How conclusive would this test be?
    Can’t find much info on how a short course of PEP like that would affect testing.
    and if the white furry tongue had been an ARS symptom would it have needed to subside first for the test to pick up antibodies?
    Thank you so much

    • Sorry what I meant to say was I took the first test 21 days after aborting the PEP and the second test a further 11 days after that

    • The test should be very accurate in spite of the PEP. Either way, you should repeat the test at 3 months post exposure.

      • Thanks very much Dr Tan.
        Still extremely anxious. Can I relax about my tongue, it has me very worried?
        Is that a usual seroconversion symptom?
        Do you think that my chances are good at remaining negative after a 4 week test, even despite the 8 days of PEP? Was worried it could delay things and mean my 4 week test isn’t as comforting as usual.

        • I think you should see a doctor about your tongue. I personally have seen many patients come to me complaining of white furry tongues and when I look at their tongues, they look 100% completely normal. So instead of worrying about your tongue, go see a doctor about it. I still think your test at 4 weeks is very accurate in spite of the 8 days of PEP you have taken.

          • Thank you so much for the advice Dr. Tan.

          • Dr Tan,
            Sorry to bother you with one more question please.
            So I’ve done 4th gen ELISA tests at 32 days post possible exposure (21 days after aborting PEP) and another at 43 past possible exposure (32 after aborting PEP), this time including a P24 antigen test, which I’m not sure was necessary because I believe the 4th gens already include this and all were negative. I plan to take another test at 8 weeks (7 weeks after aborting PEP) in the hopes it will alleviate some of my extreme anxiety and will do a final test at 3 months.
            In your opinion please, do you think I am likely to come out of this negative?

          • Yes I do. I think you are being unnecessarily anxious.

  8. Hello dr tan
    You are doing a wonderfull job and i congratulate you for the same
    Sir i recently on 19-12-14 had sex with a syrian sex worker she gave a oral to me without condom for 1 min or less and then had a veginal sex with condom then with a new condom tried to do anal for the first time in my life with her i put some olive oil on my condom and on her anus and tried penetrating he i dont remember that was i able to penetrate her fully or was just trying to penetrate as it was my first anal experience and just then i felt something and i withdrew my penis and saw the penis ( the total episode of anal was for almost 5-10 seconds), the condom broke,half of the condom was still on my penis but the front part of the penis was without condom ( that part of condom was pulled out of her anus ) i immediately went to the bathroom and washed it
    I went to the doctor nxt day and told him everything he said my chances are very rare but on my insisting he precribed me truvada alone for 30 days which i am taking regularly
    I got a rapid test on 7 day of my exposure which was negative
    HIV 1 / 2 & P 24 COMBO TEST
    Index Value 0.13
    Result Non Reactive
    I wish to know
    1. What were my chances of getting hiv
    2. Is my combo test reliable
    3. Why did it showed 0.13 and not showed 0.00
    4. Will my non reactive result convert to reativein future
    I am not having any symptoms 17 days post exposure but have had few rash like irritations on hand and back of neck for almost 2 minutes
    I am very scared kindly guide me thru

    I am very sorry for my bad english
    Looking forward for your expert advice

    • And one thing more sir is truvada alone a pep regime or it does not work that well if taken alone .

      • I forgot to mention that i took first pill of truvada within 10-12 hours of exposure . and i am unaware of the hiv status of the csw. When should i test again , and is the above mentioned test a antigen test which detects infection in 10-24 days after infection ….

    • 1. Moderate. 2. No. 3. Antibody cross-reaction. Nobody has a result of 0.00 4. It will if you are infected with HIV and your PEP fails.

      • Dr is this short exposure of high risk…?

        • Sorry to ask you again and again i am very anxious for past 17 days so just asking all these questions .
          Is truvada alone a pep regime
          Does taking truvada will effect my tests
          Antigen combo test does not result for antigens on day 14 ..?

        • And there was no blood or any kind of fluid..

          • Sorry to bother you again and again i just forgot to mention that i took the combo test on 14th day of my exposure …
            I want to know is combo test indicative on 14 day ..

          • Yes it is very indicative. But you need to repeat it at Day 28.

  9. Worried About slobbering saliva

    Hi Dr Tan

    I had a protected blowjob from a woman of unknown hiv status (I had a condom on)
    However, at some point I was holding the base of my penis and some saliva got onto my finger. There was a slight sting after that which indicated that I had a tiny cut on my finger. I immediately wiped my finger with sanitation wipes. There was no blood in her saliva.
    I have two questions:

    1) what is the risk that hiv was transmitted to me

    2) is PEP warranted in this case (I am in South Africa and can access pep if needed)

  10. Hi Doctors

    I had an incident that I drank PEP at 35 hours after incident

    I tested negative so far at the following intervals (all post exposure using 4th generation Combo test) – day 29 (immediately at completion of PEP), day 44, day 56, day 63.

    I have the following questions:
    1 .the opinion of physician capabilities with HIV do not like?
    2. these results may change at 12 weeks and 24 weeks?

    Thank you

  11. Dr tran ,

    HIV , HBV HCV test are non reactive 4 months post exposure ( 3 months post PEP) . 4th generation hiv test
    How conclusive is my test? canadian guidelines suggest testing at 6 months.

    Another question , my HEPATITIS B s Ab indicated reactive at a level of 74.260 UI/L ( Hepatitis B c Ab & Hepatitis B s Ag are non reactive) is this an infection or immunity ?

    Thank you dr tran

    • Conclusive. Most guidelines still say 6 months for people who have taken PEP. The antibody level indicates immunity.

  12. Worried SA Guy

    Hi Doctors

    I had an incident that I took PEP for.

    I tested negative so far at the following intervals (all post exposure using 4th generation Combo test) – day 14, day 18, day 24, day 29 (immediately at completion of PEP), day 36, day 45, day 51, day 69

    I have read that I need to test a 3 months (12 weeks). I have the following questions

    1) what do you think my chances are of not contracting the virus (how conclusive are my tests so far)
    2) I intend to test at 3 months / 12 weeks and just want to get clarity, should I test at 12 weeks (84 days) or 3 months (91 days)
    3) I intend to test at day 77. How conclusive is this?

    • 1. Zero chance. 2. 12 weeks. 3. Why bother? Your tests are already as good as conclusive. Don’t waste money.

      • Worried SA Guy

        Thanks Dr Tan

        Just to confirm your answer for question 1, are you saying that there is Zero chance that I will get HIV or that I will definitely get HIV? I think I might have written the question a bit ambiguously. Sorry

  13. David N. Gale

    Good afternoon Dr Tan

    I’m writing here for 2 reasons, firstly to get some reassurance from your good self (sure you must be getting this a lot) and secondly so that others reading might learn from this.

    My exposure:
    Protected vaginal sex with Russian CSW in Singapore. She was on top of me when I ejaculated, however when she got off me, the condom remained inside her. (Erection rapidly subsided after ejaculation).

    Exactly 60 hours after – started PEP. Combivir and Kaletra which would have to go on for 30 days. Currently on day 5. Side effects unpleasant. headache/diarrhoea mostly and a general feeling of malaise (which would probably be due to stress).

    I know I’ve already started PEP and will complete the dose, but based on your experience how risky would you rate my exposure? The condom was on throughout the entire duration of the sexual encounter and only “went missing” at the end. More specifically would you recommend PEP to a client who came to you with this scenario. I was thinking of going to your clinic but it was over the weekend and timings were not matching so I went to another clinic in the East.

    Secondly Based on what i’ve read in this thread, 4 weeks from exposure (PEP included) seems to be a comfortable indicator to you? My 1-month test is on Jan 10. It would be the SD Bioline 4th generation combo test. If it is negative then I shall breathe a sigh of relief.

    Thanks for letting me share my thoughts. It is indeed cathartic.
    David N Gale

    • First of all why on earth were you on Combivir and Kaletra? Of course you are going to get side effects. In fact, Combivir which contains Zidovudine is no longer recommended for PEP use because of side effects. US CDC and other guidelines have already switched to Turvada/Isentress years ago. OMG. Enough of me bitching. Your risk is about 1 in 10,000 ballpark. Assuming she is HIV +ve. I do not think it is a fair question to ask if I would have prescribed PEP or not. My PEP consultations are long and I discuss things in great detail with my patients before making a decision to prescribe. Yes 4 weeks post exposure test after PEP is very indicative. For the benefit of other readers: we are open on weekends.
      Sat 9am-1pm, 3pm-5pm
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      #02-20 The Bencoolen
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      +65 6884 4119

      • David N. Gale

        Dear Dr Tan,

        I just wanted to post a follow up here for the benefit of whoever might be following this thread.

        I completed PEP. 1 dose in the AM and 1 in the PM. Of the full month cycle, i only missed ONE morning dose as I was pretty much unwell from the PEP side effects. On that same day, I took the evening dose as scheduled. Every other single day, morning and evening doses were taken well on time.

        Immediately upon completion of PEP, I took a 4th gen test – negative

        About 6 weeks after PEP. took another 4th gen test – negative.

        I am more and more hopeful as each day passes.

        On the plus side, the entire PEP experience has made me decide to quit drinking and I haven’t had a drink since the incident.

        God bless

  14. My ALT level has been fluctuating between 70 and 94 during pep and after pep.
    Recently , 2 months post pep , my ALT level is still at 70 u/l . Is this an indication of infection ? side effect of pep ? or could me normal? ( bilirubin level very regular , AST regular , no alcohol and no smoking)

    • This is not a sign of HIV infection. It could very well be a side effect of PEP. It could also be normal. In fact, a single raised (less than 4 x ULN) liver enzyme is never something to be overly concerned about.

  15. Dear Dr. Tran
    I had a broken condom for 1 minute with an unknown lady the 11th of august 2014.She said she was clean and she refused to do tests and show me any results. I have taken PEP 8 hours after exposure and have had some ALT blood level high and EBV was detected in my blood 1 month after this ( not sure if it is a previous infection or due to this intercourse ) .

    My results for hiv came out for duo test ( including p24 )
    2 weeks post exposure ( during pep) : Neg
    5 weeks post exposure ( 1 week post pep ) : NEG
    8 Weeks post exposure ( 4 weeks post pep ) : NEG
    12 weeks post exposure ( 8 weeks post pep ) : NEG

    HOw much is my test conclusive because i have some worries about my results since Canadian Guidelines say to test at 6 months.

    • In my opinion it is conclusive already. There are still many guidelines in the world that recommend testing post PEP for up to 6 months. I think slowly this will change to reflect 3 months.

  16. desperate

    Hi Doctor,
    I visited a massage parlour and rcvd 2 unprotected oral sex from worker. Later I noticed there is a nasty pimple like wound on the worker face at the area between the chin and the lower lip on the right side. The thing is I am afraid that she might have HIV, which her wound on the face area may come into contact with my scratches wound I have on my side of the scrotum and on the insides between my thigh and testicle area as I itch regularly in that area [but it’s not red or other std types seems more like eczema (hygiene issues) and have been with me for many years] because she was s**king my scrotum and also licked the area.. I am really anxious and regret my actions terribly.. I am considering to take a PEP to lower the chance of getting HIV.From ur expertise, do you think the chances are high HIV could be contracted this way? shld I come down to take the PEP program? I just passed my 24 hours windows only. And I am really thinking about it the whole day. Pls advise I really need some help.

  17. RSAGuy123

    Hi Doctors

    You article above states that you have never seen a result that is negative with a 4th generation test at 4 weeks post exposure (immediately after completion of pep), change to a positive result later

    My questions are:

    1) are you saying that pep works all the time or are you saying that where it. Has not worked you have been able to detect infection at 4 weeks (at completion of pep)

    2) could you give an approximate number of cases where pep has worked where the source person was confirmed to be hiv positive but the patient (treated at one of your clinics) did not get infected

    3) with all the advances in hiv testing (particularly 4th generic elisa/combo), what is your opinion of why guidelines have remained stubborn at 3/6 months

    4) could you please indicate the approximate number (in your clinic only) where (due to starting late or poor adherence, the 4th generation test was able to pick up the virus at day 29

    • 1. I am saying I have detected PEP Failures at 4 weeks. 2. Many. I am sorry. I cannot reveal this data publicly. 3. LOL! Good questions man. Ask the politicians and bureaucrats. Don’t ask me. I wonder the same thing myself. 4. A few with the old PEP regimes. Again this is data I cannot share publicly.

  18. Dear Dr. Tran

    I had a broken condom for 1 minute with an unknown lady the 11th of august 2014.She said she was clean and she refused to do tests and show me any results. I have taken PEP 8 hours after exposure and have had some ALT blood level high.
    My results for hiv came out for duo test ( including p24 )

    2 weeks post exposure ( during pep) : Neg
    5 weeks post exposure ( 1 week post pep ) : NEG
    8 Weeks post exposure ( 4 weeks post pep ) : NEG

    HOw much is my test conclusive because i am very worried about it . A doctor told me to wait and redo a 6 month while the other said 4 months will be conclusive. Have you ever seen any results like this turning positive ? (PEP COMPLETED and taken very regularly and on time).

    • No I have not. I think you are going to be OK. I personally think 3 months is enough but there are some guidelines that still say 6 months. Listen to the advice of your doctors.

  19. dear sir:

    After pep started at 48 hours I am negative with combo in 23 days after completion of pep, negative with pcr rna at 15 days after pep. please advise

    • You need to repeat the combo test at 3 months post exposure.

      • First I would like to thank you for sharing this valuable information. I had a high risk exposure ( condom failure for 1 minute) during insertive vaginal sex with csw. I started pep at 48 hours. I took combo test at 30 days after exposure which came negative. During pep I noticed small white tongue at the back. On 36th day I had fever and some pimple on penis head. I took medicine for viral fever as the season was changing and lot of people were having cold and fever. Fever went away after taking medicine for two days but It came back after two days of stopping medicine. I took another combo test at 42 days after exposure and it also came negative. I went to a doctor and he told me that I had bad throat infection and my entire tongues top was white without any pain. He gave me antibiotics and fever went away and tongue color improved. Today is 56th day from exposure and my tongue is now becoming normal and i’m just doing gargles as instructed by my physician. I also had bad throat infection last year but I didn’t experience white tongue.

        I am planning to take another combo test at 27th feb i.e 60 days after exposure.

        1) Do you think my white tongue and fever were ars symptoms?
        2) Will my next result pick up antibody if I was experiencing ars symptoms?
        4) My first hiv combo test had index value 0.07 while the second one had 0.1. It’s making me nervous an anxious.

        I would really appreciate your help.

  20. Dear Dr.Tan,
    First I would like to thank to share such a information regarding transmission and tests.
    I had done severe sex with anals since 2011 to Jan 2013 after I had flu like fever,slight red rahes,Sweating&head ache decided to meet physician and concluded that I had high blood pressure(180/100).As now BP is controlled.Further I had checked my blood tests for Hiv I &II and results was Negative on Feb’14.Again the same test is repeated on sep’13 result was Negative.
    Sexual Observation:1.One time candom was broken and sperm had released but girl semen not released.
    2.Many girls sucked my organ.
    3.Lip blood had released while oral mouth sex.
    4.One time lady semen and my cutted skin blood on pennis mingle with each other.

    As my last test was sep’13 it was negative.Whether I should go for further HIV test or not?As now body condition is good except day sweating since I had Blood pressure.
    I have doubt I will be Normal or free from HIV?Even I had not followed(PEP).
    I’m very confused if any addition requirements for testing.Pls advise.

    • As far as I am concerned, your HIV tests are already conclusive. I do not see a reason for you to worry.

      • Dear Dr.Tan,
        Thanks for your reply.
        Further,I need to clarify with you regarding latest clinical report on Master health check up completed on 14.10.2014

        Clinical report as on 19.02.2013:-
        HIV I&II -Non reactive (sample serum)
        HBsAg -Negative(sample serum)
        VDRL -Non-reactive(sample serum)
        Haemoglobin – 15.7(Male.13.5-17.5)
        Total wbc count -9800 (Limit 4000-11000)
        platelet count-4.64 (limit 1.5 -4.0)
        RBC count -6.07 (limit 4.4 -5.9)

        Clinical report as on 15.09.2013:-
        HIV I&II -Non reactive (sample serum)
        HBsAg -Negative(sample serum)
        VDRL -Non-reactive(sample serum)

        Clinical report as on 14.10.2014:-
        Anti HIV I&II -Non reactive (sample serum)
        HBsAg -Negative(sample serum)
        VDRL -Non-reactive(sample serum)
        Haemoglobin – 14.2(Male.13.5-17.5)
        Total wbc count -8700 (Limit 4000-11000)
        platelet count-3.43 (limit 1.5 -4.0)
        RBC count -5.23 (limit 4.4 -5.9)

        My last sexual period since jan2011 to jan 2013.

        Based on clinical report the counts are less as compare to 2013 clinical report.I have fear that wbc count reduced as a maximum level and other counts level also.

        As now the clinical report of HIV I &II test is Non- reactive.

        One of my friend told this can be detectable even after 10yrs Is it true!? Again I request you to suggest I’m absolutely free from HIV in body or any further testing is required please advise.

        I’m so confused.

        • Your HIV test is conclusive. See the doctor who did these tests for you to explain the rest of the results.

          • It was informed to doctor and he said the changes of cells count in normal to every one on yearly basis.If any one have HIV on window period 3 to 6months or Max 1yr with the study of HIV Test I &II serum which period was already crossed by me 1.9Months.
            Doctor said not to worry.

            I ask to Dr.Tan,Is required any addition treatment as like PEP or PCR testing or Not to do any thing.Pls advise sir.

          • I agree with your doctor and as I have already said in my previous reply, I think your HIV test is conclusive.

  21. Dr.
    I had a condom break 5 weeks ago , she had endometriosis and there was a little blood there . I went to the doctor and took PEP within 12 h after exposure .About 1 week from PEP start I had candidiasis on my penis head , went straight to the doctor and he said that there was nothing to worry about because it had nothing to do with ARS . But I freaked out anyway , the caididiasis eventually went away within 2 days of threatment , I stoped the treatment then and it returned – few weeks later it was finally gone . My PEP was concluded last week ,but today (day 4 after PEP’s ending) I felt a lymphonode a bit enlarged . When I touch it doesn’t hurt , it hurts a bit when I kinda move it arround . I’ve got no fever , no sore throat or any other ARS symptoms but the nodes and a little rash – wich I don’t think is ARS rash because is only a few , not itchy and not measles looking alike at all . My point is , I’m freaking out , my 5 week test from exposure is this monday 13th , I’d like to know what is your oppinion on my situation .

    BTW Thank you for all your great informations , it helped to freak me out a little less about my” rash “. It is really better than anything I’ve read online about this subject ever . Thank you

    • The test you are going to take at 5 weeks post exposure will be as good as conclusive.

  22. Hi sir Iam hiv pcr dna qualitative test ofter 28days results non reactive and hiv 1st & 2nd screening test ofter 4, 6,8 results non reactive but ihv urine infection and I am waiting for 1month gng to I mean 9 month hiv pcr dna qualitative test result nagitive. .but iam very worried sir I need any further test sir please rly me

    • You do not have HIV. You should see your doctor about your urine infection.

      • I am feeling good sir ..ur great job sir than’Q..

        • Sir plz tel iam safe or not safe..

          • Dear Raj,
            I don’t know you are safe or not safe. But I sure that you will be alive untill you are 100 year old. So you need not worry anymore. :)

  23. Hyminh1

    Hello Dr. Tan,
    Firstly, I would like to say thankyou for your strong support me on the other topic.
    As I said on other topic, I took Pep (lamivudine & Zidovudine) within 72 hours after my first test was Negative.

    At 13rd week (90th day) after exposure, I took HIV Combi PT test (on Combas 8000 machine, made by Roche). My result was 0.18 COI ( Negative.

    At 14th week(96th day) after exposure, I took Architech HIV Ag/Ab Combo, Architech Anti-HCV, Architech HBsAg-CMIA at other hospital. My result was
    Anti-HCV: S/CO = 0.06 ( Non-reactive
    HIV Ag/Ab: S/CO = 0.24 ( Non-reactive.
    HBsAg-CMIA: S/CO = 0.29 ( Non-reactive.

    So I would like to get your advice one more time whether I am absolutelly safety with HIV or I need re-test at 6th month? My body is normal condition now as well as before exposure.

    Once again thank you very much Doctor.

    • You are absolutely safe. You do not have HIV. Dodged a bullet there.

      • HyMinh1

        Dear Dr. Tan,
        Thankyou very much. Your comment make me be strong.
        I will get it out and move on.
        But for HCV, do I need re-test at 6th month? Because I read somewhere that window period of HCV is 6 month.

  24. Hy Minh

    Hello Dr.Tan,

    I took PEP within 72 hours after exposure.
    13rd week after exposure, I took HIV Combi PT test. My result is 0.18 (COI), less than 1 => Negative.
    14th week after exposure, I took Architect HIV Ag/Ab Combo Test, my result is 0.24 (S/CO), less than 1. => Nonreactive.
    I also took Anti-HCV and HBsAg-CMIA Test at 14th weeks. All result are nonreactive.
    So I would like to ask you whether I am absolutelly safety with HIV, HCV, HBsAg or I need to retest at 6th month after exposure?
    (because I read your article that HCV can prolong the window period of HIV infection).
    I am sorry because I want to get one more your advice for my case.
    Many thank in advance,
    I hope all the best come to you.

  25. Dear Dr Tan

    Further to the above sore throat and flu I visited the local clinic where I was asked to take a PCR DNA test which I was advised is more conclusive than the 4th generation test. My question is then 1) is the pcr more effective given that my tests to 6 weeks after exposure have been negative on 4th generation test and rapid tests.

    Thank you



  26. Dr. Tan- I had unprotected insertive anal intercourse with a stranger whose status I don’t know. It was four quick strokes- I pulled out and went to a clinic for PEP. Given the low risk of the exposure (USA), they only gave me Truvada.

    I finished the Truvada with 100 percent adherence.

    My tests so far:
    – At Day 25 still on PEP I had a rapid test that was negative.
    – 4 days after completing PEP, 4.5 weeks after PEP, I had a DUO test that was negative.
    – 12 days after completing PEP, 6 weeks post exposure- I had a rapid test that was negative.

    I know I need to test out until 3 months, but are my results indicative? I’ve been worried about ARS. I haven’t had a fever or rash, but have had some sinus and headache and phlegm issues the past few days. If I was seroconverting wouldn’t I have antibodies to make my rapid HIV test positive? Or can I attribute my feeling down to the 5 international flights I’ve taken in the last 4 weeks coupled with PEP stress?

    Thank you so much for your work.

    • I should also include I began my Truvada as PEP 8 hours after my exposure and I’m a gay male who briefly penetrated another gay male in the US. Just convinced my minor headache and cough is seroconversion – though I took a rapid test an hour ago and it was negative and I’ve been feeling this way for 3 days!

      • Chill it man. You do not have HIV. Your tests are already super accurate. Stop over-interpreting your symptoms. The more you think about it the more symptoms you will have.

      • Good morning Dr.Tan,
        I am 29 yold guy. Last september 30th i had protected sex with a thai ladyboy of unknown hiv status.
        I was put on pep azt+3tc for 4 weeks.
        The first week after pep i had a labial herpes than the second week i started having many symptoms like muscle pain maybe little fever once then for 2 days then sore troath for 2 days lymph glands little swallen. Dry cough and last day headache. I got 2 weeks and 3 weeks after PEP anti hiv test at bangkok red cross hospital both came back negative but i am so scared i am experiencing ARS symptoms. What do you think?
        Thanks for your help

        • I am sure you must have realised by now your exposure was really high risk. Fortunately you went on PEP. And the 2 HIV tests you have done 2 and 3 weeks post PEP in my opinion are extremely accurate. So the chance of you having HIV is miniscule.

  27. I have found this update from US CDC. It is said the follow up testing may be concluded at 4 months if 4th generation test is used.


    I have got my HIV test from week 16 via E.C.L.I.A ab/ag. And it is negative.

    However, I have concern regarding to my Complete Blood Count. It showed that my WBC is 6900 and lymphocyte percentage 19.2% with absolute count of 1325, which is lower than the normal range (1500 – 4000) from the lab.

    Another concern is that I was a bit over 67 hours late for PEP, but still within 72 hours. My baseline CBC showed that my WBC is 8650 and lymphocyte percentage 12.4% with absolute count of 10735, which is lot lower than normal range (1500 – 4000) from the lab. My Neutrophil is normal on week 16. All other number in CBC are good.

    My HCV and HBV test via E.C.L.I.A at week 16 is Negative. I did not take any drugs or having any cold. My Neutrophil is 78% (a lot higher than normal range). All other number in CBC are good at baseline.

    Few questions I want to ask from your expertise.

    1. Does the CBC test at my baseline of PEP hint anything serious issue?

    2. Dr.Tan, Normally do you perform CBC for your PEP patient? If yes, did CBC hint anything to HIV infection? (taken my CBC number as example)

    3. That’s an updated poster from US CDC updating said 4 months is enough for following up if 4th generation test is used. My week 6 test was normal ab test. I only got the 4th generation test three times on week 9, week 12, and week 16. You said in your forum that p24 drop after 6 week. So I worry that the US CDC mention that 4 months is enough, but this does not count in my case… as I only did 4th generation test after 6 week. Do you think I need to retest at 6 months mark?

    Thank you for your answer.
    I hope my worry is only just worry…

    • 1. No. 2. Yes. No. 3. I think your 4th Gen test at 6 weeks is already conclusive. However, officially I test up to 3 months. How long you should follow up for depends on your doctor. Please ask him on your next follow up.

      • Thank you Dr.Tan,

        Actually my week 6 test is only ab test. The combo test are on week 9, week 12, and week 12.

        My doctor said 3 months. But due to many information on internet and different guidelines from many countries… make me worry and confusing.

  28. Dear Dr. Tan.
    Greetings from India,
    First of all i would like to thank you for the wonderful work you are doing and i would like to apologize for my bad English.
    I would really appreciate if you can help me 6 weeks ago i had a low risk exposure fingering a sex worker in Mumbai i had a small fresh cut on my finger i insisted on the doctor to give me Pep i started it 65 hrs after exposure.
    -20 days after exposure i did a DNA PCR qualitative test the result was: Not detectable , my doctor said it was conclusive and to stop Pep but reading online i realized that while on Pep we can have a false negative especially that i had a sore throat for almost 4 weeks after exposure
    – 39 days after exposure , 10 days after finishing Pep i did an Elisa test (4th generation) also the result was : Not detected .
    Should i do further Testing ?
    6 weeks now after exposure i still have ulcers on my tongue , joint,muscle and stomach pain is it HIV early symptoms or Side effects after stopping Pep ?
    Thank you

    • You were not even at risk of HIV in the first place. I do not see a reason for you to worry.

  29. Dear Dr Tan and Partners

    Firstly thank you for the very informative site and blog, it’s greatly appreciated. I have read all the posts above and the respective comments and your responses too which are quest informative to the uninformed.

    I have also noted that no cases above are similar. I myself have been exposed as follows:-

    I had varginal sexual intercourse on 05-06-2014 which started of with lots of foreplay with my female sexual partner releasing varginal fluids which I touched with both my hands and male organ and then without drying used the same hands with sexual fluids to wear the condom. I was the insertive partner with her being on top the intercourse lasted a few minutes approx 5 minutes. On completion I noted that she had released an abundance of sexual fluids which I wiped and discarded the condom.

    24 hours after the incident we confirmed she was positive and I negative via rapid tests. At the same time I was started on a Pep regimen of Lamivud/Zidov and Lopinavir/Ritonavir on 06-06-2014. I reacted terribly to the combination with diahoreah and the regimen was changed on 07-06-2014 to Truvada and Instress for 30 days and a single once of dose of Zithromax. All base line tests done were negative. On 27-06-2014 I developed a sore throat,29-06-2014 excessive sweating at night, on 02-07-2014 developed a genital pimple on my inner thigh which dried the following day, was tested 6 weeks on 14-07-2014 hiv 1/2 rapid negative and hiv 1/2(4th gen)-negative I am hove ever experiencing joint and muscle pain and lower abdominal painon and off during and after pep treatmentto date, I have also had a flu infection sore throat with white sputum and mucus that hasn’t responded well to flu medicine and amoxylin antibiotic for three weeks now.

    My questions are 1) could I have been exposed indirectly by the sexual fluids on the organ and hands when I wore the condom 2) could I have delayed sero conversion sickness due to the muscle ,joint and abdominal pains 3) what are the chances of the next test results on 04-09-2014 changing to positive thus far

    Your usual help and assistance will be greatly appreciated as I’m confused and lost

    Looking forward to your favourable response



    • 1. I don’t think that is a relevant question. I think you are at risk simply because I know condoms are not 100% effective. That said, I think your risk is extremely low. 2. You are assuming your symptoms are due to HIV seroconversion. I do not think this is the case. 3. No chance. You are OK. Don’t worry.

      • Dear Dr Tan

        Msny thanks for the response it’s highly appreciated and acknowledged. I have however also discovered lumps on both my upper rib cages both the left and right, and these are painful when touched these are situated way below the armpits but before the end of the of the ribs, could this be an hiv related symptom.

        Lastly after how many weeks is an rapid hiv test conclusive in the absence of elisa test

        Thank you once more


        Thandi T

        • Again your question on symptoms is not relevant. I honestly think your tests are already accurate. However, because you took PEP, officially you must test till 3 months post exposure.

  30. Januário

    Hello Docs,

    I work as paramedic in ambulance at peru, almost one year ago i hurt myself when i help a pacient, he was hiv positive.

    I’ve iniciate PEP 2 hours after for 28 days, and done the following tests

    1) 4 weeks post exposure Duo Test-Negative
    2) 8 weeks post exposure Duo Test-Negative
    3) 12 weeks post exposure Duo Test- Negative
    4) 16 weeks post exposure Duo Test- Negative
    5) 20 weeks Post exposure Duo Test -Negative
    6) 26 weeks (180 days) Post exposure Duo Test Negative

    Per law and insurance, i have to take one more test at one year, i want to know doctors, if you have seen at your clinic, someone change result between six months and one year. Thank you!

    PS, sorry for my bad english, i never study, learn it at movies ;)

    • My friend your English is superb. Thank you Hollywood. I am utterly convinced that you do not have HIV. I think your tests are more than enough to be conclusive. Please do not worry about your test at 1 year. I am sure you will be fine. You inspired me to read up on Peru. It is a most beautiful country.

      • Worries123

        Dr. Tan,

        I think Januário is so brave to take the test monthly. No many can do that… I wish him good luck and good health.

      • Januário

        Thank you Doc, i hope to know Singapore one day, it’s a fantastic country!

  31. Worries123

    Hello Dr.Tan,

    I know you’re always keep up to date of current researchs. If a Combo Test on week 12 from exposure is Negative… Base on your knowledges and expertist, do you recommend re-test?

    If you do recommend re-rest? What is the reason?

  32. Dear Dr. Tan,

    4 days ago, I had a sex with guy working in massage shop ( I just have strong feeling that the guy is NOT clean – might HIV+) I we hand protected anal sex then I sucked him unti he cum in my month. Sorry for being descriptive this way.

    My questions:

    Is my sexual contact considered high risk exposure?

    Do I still have a chance to start PEP? After more than 72 hours

    I would really appreciate you prompt response

    Best regards

    • Yes. Absolutely. Anal sex is the highest risk sex act. There is no point starting PEP after 72 hours.

  33. Dear Dr. Tan,
    Apologies for the long post.
    I am one of the many people who have approached you for a counsel in Sept 2013. I would please like to share my experience.
    My exposure was a condom burst incident with a CSW, I was on PEP at the 21st hour after exposure. I had a positive qualitative RNA PCR from a blood draw taken on the 12th day. My doctor had advised me that this indicates an infection and that I should stop PEP, all my research indicated that the PEP should be taken for 28 days so I continued against the doctors advice.
    I had a second blood draw on the 16th day which was undetectable. I was very apprehensive at this point and didn’t know who to approach for advice. Seven weeks after PEP I had a fourth generation Ag/Ab test which was non reactive. The information available on the Internet was contradictory and to top this I work in a middle eastern country with archaic laws on HIV tests.
    It was at this point that I approached Dr. Tan for his advice, he advised me that I did not have to worry since I had a non reactive test at the seventh week after exposure, no one else was able to give me an assurance or hope except Dr. Tan, To top this I had an case of urticarial rash and a a fever for 3 days at seven and eleven weeks after exposure respectively.
    The problem was that I work in a middle eastern country with archaic laws on HIV testing and could only take leave in July 2014 which was 11 months after exposure. For the last ten months, I used this page every single day must have been here a million times and this was the only thing that used to calm me down. Today (eleven months after exposure) I had a fourth gen Ag/ Ab test which was non reactive, thank god.
    Dr. Tan I cant thank you enough, you were the only person who had given me hope. I have immense respect for your selfless work. I wish you the very best in life, I would be delighted if I can make an humble contribution to your noble cause.
    As for me I have learnt my lesson, this was the first time that I had visited a CSW and never again, It was a harrowing experience.
    Thank you very much Sir.

    • I am very happy you are well and am equally happy we could offer some help to you during our ordeal. Thank you very much for sharing your story. That is all the contribution we need.

  34. Lorenso

    Hi Dr Tan,
    After taking PEP for 28 days some say to get a conclusive result one has to test after 3 months from the date of exposure. Does this mean that from the date that the exposure happened or from the date that last dose of PEP is taken. Please help to understand this. I am thinking of doing a quick combo test at your place , but need to get these dates correctly understood. Thanks Thanks! Lorenso

  35. Dear Doctor Tan,
    I send you a comment in july 6 2014 and i want to inform you about my new test i have after 2 months of my exposure with 4th generation ab/ag test which is negative.
    My first question is the last test conclusive?
    Also i read from this site http://i-base.info/ that someone who have test one month post pep is 95% accurate with 4th generation test and if someone wants 100% result must wait 3 months after finishing PEP.
    Thank you.

    • According to new guidelines, patients post PEP must test up to 3 months to be 100% accurate.

  36. Chucks

    Hello Dr. Your good works obviously stands out.
    Please i need your honest opinion. I know 3 months test is conclusive based on official guidelines However have you ever seen 8 weeks negative antibody test ( 4 weeks post PEP) change. How conclusive can I believe this will be based on your experience.


  37. Hello Doctor Tan,

    I found your website while I Google. It is very useful and extremely helpful.

    I was on PEP on day 3, and almost 70 hours late. My testing are all negative:

    – Week 6, ab test
    – Week 9, ab/ag Combo Test
    – Week 10, ab test for Hep B and Hep C
    – Week 12, ab/ag Combo Test

    Again, all these tests are Negative.

    Due to location matter, I did not get to follow up with my PEP doctor. The last thing I remembered is he said 3 months test is enough.

    I’ve been having many ARS look-like symptoms and I still feel anxiety suffering from having watery stool every morning soon after my coffee.

    Because I did not get to follow up with my PEP doctor. I would like to apologizingly ask few questions:

    1. Does the morning watery stool after coffee look serious? Honestly I’m not sure if it’s due to Stress… I can’t control my feeling recently.

    2. Do the different PEP drugs make different window periods?

    3. You mentioned many times above that 12 weeks or 3 months are conclusive. So does this also count in my case?

  38. Johny

    Dear Doctor, I have an anal sex with a unknown hiv status person after 14 hours i take twice a day kaletra and once a day truvada.I have completed pep for 30 days and i have two hiv tests,the first test take it after completion of the pep (30 days after exposure or next day after pep) also the second test i do it in 3 weeks after pep or 7 weeks after exposure(all tests are negative).i have some questions about tests. How accurate are the last test i take and also i need to repeat test a 3 monts

    • drtan

      Very accurate but not conclusive. Yes you need to repeat the test at 3 months.

  39. Lar (Male)

    Dear Dr,

    I have been having a hard time for the past couple of weeks due to one particular incident. I know I did something very wrong and suffering from the outcome. It is really difficult.

    On 3rd of May (Friday) I had an encounter with a Filipino trans sexual sex worker in SG.There was absolutely no penetration involved , but I received oral sex from this person with a condom on and it was intact (condom had a reservoir tip , I hope this is a non animal skin condom :( ). The only other act was I sucked this SW breast but it was not a serious sucking , more like I was licking her nipples.

    Having done this I got freaked out and I ran to a doctor next day and insisted on PEP. Doctor did not prescribe but I really insisted so he gave me 28 days PEP (Combivir and Kaletra) and I completed this.

    After the completion I had a rapid anonymous (Ag/Ab combo test , 4th Gen) test at your place after completion of pep (38 days from the exposure ,9 days after PEP ). The result came negative and the lady doctor said this is 99% accurate.

    I am very afraid to go back to the doctor who prescribed me PEP because if I find positive I do not know what I should do being a foreigner here

    could you please help me get out of this misery , I am unable to focus due to this constant fear of hiv. I tend to check my self every now and then to see symptoms and I am going crazy now!

    1. Doctor do you think I was at risk ?
    2. The test I did after PEP , is it conclusive ?
    3. Do I need to test again after 3 months post exposure ?
    4. What would be the chance that this result may change in 3 months?
    5. Do animal skin condoms have reservoir tips similar to latext ?

    Doctor please please help me!


    • Dear Lar,
      You’re worrying yourself too much.
      1. Your risk in the first place was negligible. By CDC standards, receiving oral intercourse with a latex/polyurethane condom on is a zero risk event of getting HIV. Even receiving unprotected oral sex is considered a very low risk event.
      2. Yes, your test is conclusive.
      3. You can retest if you want to, but I don’t think there is a need.
      4. In your case, nil.
      5. Reservoir tips are a design feature specific to the manufacturer and make of the condom rather than the materials used as far as I know.

      • Lar (Male)

        Thank you doctor , It was a very relaxing statement and I hope you understand how much it means. I would never ever ever again do this kind of foul act certainly. The agony was too much and I really could not put that into words. Much kudos to you and your team.

  40. Hiv antigen and antbodies after 28 days but while on prep.
    Dear doctor,does pep alter the results of antibody and antigen test done during the last day of pep(it was dose 29 out of the 30 indicated)?

    • There is a theoretical possibility but honestly I do not think the PEP affects the tests at all.

  41. worriedsick123

    Dear Dr,

    I would like to ask you my theoretical risks regarding my story with a girl of unknown status.

    1. I had unprotected oral sex (bj) for about 10 secs.
    2. I properly used the condom for vaginal sex, but then lost erection because I was drunk, so I took it off. Then I masturbate myself to get an erection back and put the *used* condom back on. *There I am not sure if I put back on the wrong side.* Upon realizing it is not good to reuse the condom, I took it off after not longer than 3 seconds.
    3. Then I took out a new condom and had vigorous sex for maybe 15 mins.

    Can you tell me my risks?
    For scenario 1, am i at risk?
    For scenario 2, i am really worried since i could have touched vaginal fluids if i put on the wrong side. Please help.
    For scenario 3, I think I used the condom right because I checked it after and saw semen inside. Also tried to push them out but the condom is intact. So is it safe to say its OK?

    • drtan

      1. No. 2. Condoms are not 100% protective. You are at risk but not because you touched the vaginal fluids. 3. No. Please read: http://www.drtanandpartners.com/how-effective-are-condoms-diaphragms-and-circumcision-in-preventing-hiv-transmission/#.U40fFLr2MeE

      • worriedsick123

        Dear Dr Tan,

        From the link, I understand that I am at risk for No. 2 because I didn’t check if he condom was intact? Whereas for No. 3 I checked so I didn’t have a risk? Is the assumption correct? (For the record, the condom I used was latex: does it make a difference?) I am a bit confused as to a difference in your answer to No. 2 and 3. Can you please calrify? For No. 2, my worry was that my penis might have touched the vaginal fluids which could have gone inside the urethra when I resumed having sex after putting on a new condom.

        Regardless, I did take PEP after 17 hours of possible exposure (DuovirN – for two days) and then switched to Duovir for another 28 days. I couldn’t get top of the line PEP as I am in a third world country. So, now I am worried about the efficacy of the generic PEP. Can you shed some light on it?

        I had a P24 Ag/Ab test 18 days after possible exposure and another one at 33 days after exposure. While taking meds, I had a sore throat on 16 days and fever of 100.5°F as well as bad taste in mouth and night sweats. Also currently 34 days after, I am having another sore throat, cough and sneezing, no fever though. Could these be due to ARS? Can you help?

        • worriedsick123

          Dear Dr. Tan,

          I meant to say I had two combo tests at 18 and 33 days after possible exposure and received nonreactive for both tests. Can you please just clarify on my first paragraph though if you don’t want to discuss symptoms (since they are not reliable anyways.)

          I have been very anxious and depressed Dr. Tan. Every single day all I can think about is this issue of possibly having contracted HIV. Sigh.

  42. Hello Dr.Tan,

    I just finished my 28 days PEPs today with combination of Kaletra & Combivir. I took PEPs at around 68 hours post exposure.

    My story was, I had protected vagina intercourse and unprotected oral sex (I am receiver). I have few questions:

    1. Was my risk of getting HIV infection high?

    2. When should I get my test for HIV?

    3. I am uncircumcised. Will this adding more risk to my condom usage?

    I hope I can get answers soon. And million thanks.

    • drtan

      You obviously did not take those meds from us. Those are the old regime and honestly the US CDC now even recommends against one of the components in these meds for use in PEP. I suggest you go back to the doctor who gave you these meds to answer your questions.

  43. beebz


    I was just wondering the possibility of ARS symptoms occurring after 28 days of PEP completion? Would they already have happened by now or would PEP have halted seroconversion until after the PEP has been completed?

    I’m freaking out a bit. I’m receiving my test results next week, 28 days post exposure, but when my blood was drawn, I still had one more dose of PEP left.

    Will still being on PEP have an effect on these results?

    If I could please have your professional opinion I will be so grateful.

    • drtan

      Whether or not ARS develops really has nothing to do with being on PEP. There is a lot of theory on PEP affecting the HIV testing window period but none of this has been proven. In my own experience, a HIV test immediately following the completion of PEP is extremely accurate.

  44. worriedSA

    I used a 4th generation elisa test.

  45. worriedSA

    Hi Dr tan,

    hope you have been well ?
    Dr tan I did my test a 5 months after exposure and 4 months after PEP it was negative, can I consider my results conclusive ?? pls advise, take care

  46. ScaredEc

    I double checked dates, they are corect.

    January 2014 he had his routine HIV test and was NON REACTIVE.

    April 01, 2014 I had my routine HIV test and was NON REACTIVE..

    April 12, 2014 Condom broke.

    April 13, 2014 We both took 4th generation HIV test and it was NON-REACTIVE.

    Thank you for your answer Doctor. I don´t usually get flu like symptoms and I had the flu shot in January. I have had a sore throat and the tonsils swollen since the incident. Are tonsils lymph nodes? I have no other symptoms. Do ARS symptons come all together or can someone just have one or two?

  47. ScaredEc

    Hello Dr. Tan,

    Greeting from Guayaquil, Ecuador. I saw your page on a HIV blog here, where they recommended you as one of the best.

    I am extremely worried and people say I am crazy.
    I am a 28 year old gay male, and I had sex with a 25 year old gay male. On April 12/2014 I was the insertive partner (I was top) we used a condom for sexual intercourse and just when we were about to finish, we changed positions so i had to take my penis out and insert it again. We had sex for around 3 or 4 minutes more until we were done.
    It wasn´t until i pulled out my penis at the end that I realized that the condom had broken and I came inside of him.

    We both worried but I had just had a 4th generation ELISA on April 01/2014 and it was Non Reactive so the guy calmed down but his last HIV test was on January 2014 (around 4 months ago) he told me he always protected himself and had never had a broken condom in the last year. We went to take an HIV test but the results came back next day, so after that I went to a Hospital and started PEP (ATRIPLA)inmediatly at 3 PM before 20 hours of exposure and they told to wait for his results.
    His 4th generation elisa results came back Non Reactive and mine did too. But before we got the results, I started thinking “what if he is in window period and he has a false negative” I have known the guy for MONTHS and we have had sex a few times but I just got anxious because of condom broke and we were not exclusive. So when I received the test results NON REACTIVE, they did not calm me down. Of course the hospital took me out of PEP and said that since he was HIV negative I didn´t need to do PEP and the fact that we used a condom and it broke at the end, was safer because the penis did not had any friction and was intact (I applied alcohol after I realized the broken condom and it didn´t hurt so I had no laserations) They examined his throat and his glands and said that he had no indications of being in the window period. But I was still quite worried. Of course I started touching my lymph nodes every 5 minutes and overeacting over anything I felt, and 3 days after condom broke, I started feeling two lymph nodes on my neck on the both sides and I got so worried I even felt nausea when I found out my lymph nodes were swollen.

    Is it possible to have this sympton only 3 days after possible exposure? is it possible to have any ARS sympton after 3 days of exposure? is it possible that I created this swollen lymph node by stress or by touching it? Am I crazy? I am a bit hypocondriacal I must admit, but I can´t seem to calm down.

    A friend of mine, she is a Doctor, and she tells me I am somatazing symptoms; that it is impossible that I have ARS because the guy was non reactive and even if he was in window period, which she thinks it is unlikely because of his examination of throat and lymph nodes, it is still to soon for symptoms.

    Can you please give me your opinion Doctor Tan. I am desperate.

    • First of all I think you got your dates wrong. But never mind that. I completely agree with your doctor friend that your symptoms are probably born out of your anxiety. It is impossible to have symptoms of HIV infection 3 days from the exposure. In all likelihood you were not exposed to HIV in the first place.

  48. hi dr Tan

    It would be greatly appreciated if i got your opinion on my situation. I had a sexual encounter about three months ago. I went on pep 48 hours later and completed the 28 day course. I then had an antibody rapid test done the following day of completing the pep. Yesterday was the 3 month mark after the exposure (2 months after) pep and I had an hiv pcr rna test as well as an antibody rapid test. Would you say my results are conclusive?If not, what are the chances that im clear of hiv and could you tell me if there is anymore tests I can do now to ultimately stop me from testing further down the line.

    Thank you in advanced for your advice

  49. Hello Dr. Tan

    I’m from the US. I had receptive anal sex with another man. We used protection but the condom ended up rupturing and we didnt find out until after he came inside of me. He came a lot and I freaked out because he is known to be HIV+. I quickly went to the ER and got on PEP (Atripla) for the 28 days. As soon as I was done, I took an Oraquick test at 4 weeks post exposure and that came back negative. I then waited and took another Oraquick test two weeks later (6 weeks post exposure) and it also came back negative. What are my chances that my 12 week test will come out negative as well? Thank you so much for all your hard work!

    • I think the 2 OraQuick tests that you have done are already very indicative. Personally I think there is no chance that your test at 12 weeks will be positive. I think you have well and truly dodged this bullet. That said, please still go for your 12 weeks test.

  50. Hi dr

    3 months ago i had a sexual exposure through unprotected intercourse. 48 hours late i started the three in one pep regimen which i completed 28 days later. The next day i took a rapid antibody test which came back negative. 9 days later I took RNA test which also came back negative. 17 Days after completing the pep I took another RNA test which came back negative.Yesterday was the three month mark after exposure and did a rapid antibody test which came back negative. Do you think these results are conclusive?if not whats the confidence i should have in all my tests done? And is there any test I can perform NOW(such as another RNA test) that will allow me not to have any further tests in the future.

    Thank you in advanced for your advice


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