Dr. Tan and Partners is one of the few approved Anonymous HIV Testing Centres in Singapore. A detailed write up on our service is available here.

Other STD services: Early STD Screening, Rapid Hepatitis B Blood Test, Swab for Gonorrhea and many more... contact us to make an appointment now!

HIV PEP treatment at our clinic

If you have had a high risk exposure to HIV in the last 72 hours read on.

You are a potential candidate for PEP if:

  • You have been exposed to potentially HIV infected body fluids
  • Your exposure was less than 72 hours ago

Factors that can increase the risk of HIV infection include:

  • Condom Break
  • Presence of Blood (e.g. Menses)
  • Presence of cuts
  • Presence of Ulcers
  • You are not circumcised

International PEP Guidelines

What are the HIV PEP Guidelines? According to the WHO Guidelines on PEP, the following criteria apply: Individuals are eligible for HIV PEP if: • exposure occurred within the past 72 hours; and • the potentially exposed individual is not infected or not known to be infected with HIV; and • mucous membrane or non-intact skin was significantly exposed to a potentially infectious body fluid; and • the source is HIV-infected or the HIV status is unknown. According to the NYHD HIV PEP Guidelines, HIV PEP treatment should be recommended in the following exposures: •Receptive and insertive vaginal or anal intercourseb •Needle sharingb •Injuries with exposure to blood or other potentially infected fluids from a source known to be HIV-infected or HIV status is unknown (including needlesticks with a hollow-bore needle, human bites, accidents) According to the same NYHD HIV PEP Guidelines, HIV PEP treatment should be evaluated on a case-by-case basis in the following exposure scenarios: •Oral-vaginal contact (receptive and insertive) •Oral-anal contact (receptive and insertive) •Receptive penile-oral contact with or without ejaculation •Insertive penile-oral contact with or without ejaculation Factors that increase risk: •Source person is known to be HIV-infected with high viral load •An oral mucosa that is not intact (eg, oral lesions, gingivitis, wounds) •Blood exposure — it is important to note that blood exposure can be minimal and therefore not recognized by the exposed person. If the exposed person reports frank blood exposure, PEP would be indicated These are just guidelines. The ultimate decision on whether to start PEP or not requires a detailed analysis of the risk benefit ratio. You must have this discussion with your doctor in a formal medical consultation.

What HIV PEP drugs do we use?

We use the current first in line HIV Post Exposure Prophylaxis Medicines with fewer side effects and better HIV prevention. This is in accordance with the latest International Standards. 

We use a variety of different Anti-Retro Viral medications in various combinations based on a patient’s specific circumstances.

We do not believe in a ‘on-size-fits-all’ approach.

Although different medicines are used, they all have to be taken for 1 month.

What are the HIV PEP side effects?

With the new PEP Drugs we use, side effects are very rare. Fewer than 1 in 100 of our patients actually develop any side effects.

Common (< 1%) side effects include nausea, diarrhoea and feeling very tired.

Rash and fever are uncommon (< 0.1%) side effects.

There is a theory that these drugs can affect the liver and kidneys temporarily so these have to be monitored.

We routinely monitor all patients who take PEP but have never come across anyone develop kidney or liver problems with the medicines.

The new HIV PEP Drugs that we use have fewer side effects compared to old medicines. Make sure you know what drugs you are taking before you start on the PEP.

How much does the HIV PEP cost?

The usual costs involved are:

  1. Consultation $60-$80
      1. Depending on the duration of the consultation
  2. Blood tests (Full Blood Count, Liver Function, Kidney Function) $140
      1. These tests are to establish a baseline
      2. We do not need to wait for these results to start the PEP treatment
      3. You may not need these tests if you had them done recently e.g. when you did an executive health screening
  3. Rapid HIV test $50
      1. This is to ascertain that you do not have an established HIV infection
  4. Medication $1800
      1. This is for the entire 1 month of medication
      2. The price is the same regardless of which drug regime we use

Total cost $2193.50 – $2214.90 with GST Maximum

If you do not require the blood tests (e.g. you have done them recently) the cost will be lower.

So what now?

If you think you are at risk of being infected with HIV, come down to see us as soon as possible.

We will have an in depth discussion with you on your risks and whether or not it is recommended that you take PEP.

We are a walk in clinic, you do not need an appointment


Need more advice?

Come down to Our Clinics for a discussion with Our Doctors, or call our clinics for more information:

1.) Robertson Walk (Anonymous HIV Clinic)  (+65 6238 7810)

2.) Bencoolen Street (+65 6884 4119)

3.) Novena Medical Centre (+65 6397 2095)

4.) Somerset – Orchard Building (+65 6262 0762)

5.) Raffles Place – PLUS (+65 6962 7144)

6.) Holland V (+65 6235 1339)

7.) Siglap (+65 6962 2144)

Where to find us – here

Selected clinics are open on Saturday and Sunday.

Email: hello@dtapclinic.com

All Our Doctors are Fully Certified and Trained to conduct specialised STD Screening,  STD Testing & STD Treatment and HIV Testing.

For lady patients who prefer female doctors, we have professional certified female Doctors to attend to your medical needs.

We are Open on Weekends.

Our Andrology and Infection Centre at Novena Medical Center is open.

Call us at 63972095 now to book your appointment.



  1. Had unprotected oral sex but protected sex with ejaculation. I pull out condom but it was stuck inside her (not sure how deep in) then the tip of my touched some vaginal fluid on my pubic hair. Should I be worried?

  2. Hi Doctor,

    I had unprotected vaginal sex 10 days back. It was only for 5 seconds. Then we stopped. I did not ejacuate neither did she.

    Since day 1 after exposure I am feeling tired. I am continuously feeling tired since 10 days. Just tiredness and fatigue not even fever.

    I got HIV RNA test which will be available in four more days. But am bit worried. Is being tired for continuous since exposure, a symptom of HIV? By the way, my partner had Pneumonia 25 days back. Please let me know.



    • You should have asked your doctor if your tests were conclusive.
      Based on your description, I do not think you need to re-test.

  4. Hi doctor,
    I am 25yr male last week had a protected vignal sex with geylang street walker( singaporean) during vignal intercourse my condom broke that I didn’t know, after ejaculation i came to know condom failure my intercourse timing less than 3 mins according her status she say don’t hav hiv but i don’t believe her , i stopped sex i washed my penis only with water and i ran to clinic within 1 hr , doctor tested me with hiv combo test antigen/antibody test it came negative then he started pep within 2hr of my exposure with Truvada & Isentress , but by the time I consumed alcohol (only one can beer),
    pls advice me
    1. Is alcohol can affect pep?
    2. How effective my doses are??

    • I am on the 8 th day of pep so far i don’t experience any side effects , I am planning to do HIV I&II with p24 antigen test after the 50th day of my exposure is that test will be indicative?

    • You have to direct these questions to the doctor who prescribed the PEP for you. We cannot give medical advice over the internet.

  5. I am curcumsized male. Had sex with a prostitute 15 days back and my condom broke which was noticed after ejaculation. I asked her status and according to her she do not hav hiv. But now i hav dry itchy skin rash on top of feet. Stomach gas problem and lack of appetite and muscle ache and fatigue and blur vision. I do not have fever or diarhea. I am too much stressed and feeling angry on myself. I am also started taking PEP after 21 hours of sex. Please suggest test and guide plz.

  6. PepAndScared

    Hi doctor, I think I might be the next case where PEP failed. I had a broken condom incident whereby i was the insertive partner for vaginal sex with a female friend. An hour after the broken condom we found out she is positive because we both went to get tested (she never knew she was positive). I started PEP within 5hrs. After one week of completing the 30 day PEP program I developed phlegm that gets stuck in my throat a lot as well as one swollen lymph node next to my Adam’s Apple (confirmed by the doctor). These symptoms have remained with me for 4 weeks and medication hasn’t helped at all. The skin around my mouth has also turned a dark red/purple and has been that way for 4 weeks as well. I’m waiting for my 6 week test. Ive given up all hope.

    • You’re over-reacting. Don’t scare yourself unnecessarily and just go get tested. Nobody knows if you are infected with HIV or not despite your symptoms. Even if you did not have any symptoms it also does not mean you are not infected. In other words, letting yourself sink into this kind of horrible mental state based on nothing (yes your symptoms to me are nothing) is just being self destructive and not helping the situation at all.

  7. Hi Doc Tan
    During my stay in Singapore I had sex with a massage girl in Orchard tower and I was drunk at that time. That time when we had sex I noticed that she used a condom from a tissue paper. As I was drunk I didn’t know what to do so I proceed with having sex. We had penetrative Sex for maybe 5 minutes. But on my way back home I was worried a lot. What if the condom was a used condom. But one observation is that the condom was rolled properly when she took the condom out of the tissue. Do u think in affected? Coz I’m worried. But I read in Internet that HIV virus dies instantly outside the human body host including those in the semen. So am I safe ? I need ur advice Awaiting ur answer sir

    • What you are worried about is if there was infected semen on the condom and it was transferred to you. I have not heard of anyone getting HIV that way. What I would be concerned about is a higher risk of condom failure from using a used condom. Even if there was no obvious break, tears or slips, condoms are shown to be about 87% protective against HIV. At the end of the day, the only real way of knowing if you are infected or not is to get tested.

  8. Does tests around the world are the same. I have an exposure in Mexico and got tested on Spain. 4gen test after 3 months- negative.

    • Not the same. There are many different brands and types of tests. All of them have their own unique testing characteristics including sensitivity and specificity. If you want to know the accuracy of the tests you have done, the best person to ask is the doctor who did your test for you.

      • I know the test. What i mean is that if i got the virus in another country of mine, will still show if i test in amy other country?

  9. HEY Doctor,
    My friend is HIV POZ but has been on the Antiretroviral therapy for the past one and a half years…. she also has achieved the non detectable load status. I, on the other hand am HIV Negative. We had non protected anal sex, later to figure out I had a cut on my dick due to stretching of my skin. Is it possible for me to contact HIV ??

    • Yes it is possible but extremely unlikely. First of all, the fact that she is on ART reduces the risk of passing it to your significantly. Secondly, the risk of getting HIV from insertive anal sex is low anyway. So overall your risk of HIV is low. If you wish to continue having a sexual relationship with this partner, you may want to consider PrEP. Click HERE for more info.

  10. Doctor I have an oral sex with sex workers in a Month I stat losing weight and I have rashes at my back I went for HIVt test and my result antibody for HIV is 1.00 non reactive band HIV ab/ag is 0.15___1.00 reactive and the doctor didn’t give me any medicine for HIV and sin then am having flu and other signs is my result confirmed positive

    • What? Did the doctor not tell you? What kind of doctor lets you out of his clinic without even telling you if you have HIV or not? According to most guidelines, any positive HIV screening test has to be verified by a confirmatory test. Please go back to see your doctor for more advice. Better yet, go see another doctor who is better at taking care of HIV related testing matters.

  11. Dr please am yet to get a response to my earlier post. i was exposed to hiv positive partner and i started PEP at 68hours after exposure. Please what is my fate after 28days PEP?

    • PEP is effective within 72 hours from exposure. However, it is not 100%.
      Complete your PEP and get a HIV test done.

    • Mark Ryan

      Dear Dr. Tan. I cannot thank you and your staff enough for the wonderful material that you have here. I’m on a 28 day course of pep (Truvada + Tivicay) for RAI with no condom (stupid me…I didn’t look to see if his condom was on). Went straight to emergency and got on pep within 2 hours of possible exposure. The source claimed to be hiv neg one month prior but had had RAI without a condom two weeks prior to our hookup. This means that if he is positive, his viral load is likely high and the Infectious Disease specialist said my risk was 6%, even without ejaculation. Yikes. I’m trying to find out how effective I may expect the pep to be. You stated that you had one failure. How many courses of pep have you prescribed that have been completed properly and with the patient on “good bevhaviour” (i.e. no additional high risk exposures while on pep)? I’m trying to figure the efficacy of pep in your experience, expressed as a percentage. Thank you in advance.

      • Hi Mark. Thank you for the well written and extremely polite post. I really appreciate it. We are also happy you find the information here useful.

        I completely agree with your ID Specialist and I think I know which source he is quoting from.

        I have prescribed hundreds of courses of PEP. I have never seen a failure IF the PEP is given within 72 hours of exposure AND the patient takes the medications on time and regularly. So my experience for the success of PEP given the above caveats presented as a percentage is 100%.

        The only difference I would point out is that I use Isentress in place of Tivicay. The are both integrase strand inhibitors. And in treatment studies, Tivicay has been found to be better. So I doubt there is a significant difference in efficacy when used for PEP.

        • Mark Ryan

          Dear Dr. Tan, Thank you so much for the time to reply and to share your insight. Since the time of my original question to you, I have learned that my source had a Duo (p24 + antigen – 4th gen) test done a week ago and was negative, although this is a very inconclusive result at what would have been two weeks post his exposure. I did message him today to ask if he had experienced any flu-like symptoms since we had met, as he would now be at the one-month mark from his own possible exposure, and his reply was “no symptoms”. I’m digesting this as favourable news as he has a greater probability of being negative, due to no symptoms. Forgive me for questioning you about Pep’s efficacy again, but you did report once about a Pep failure where you and the client were stunned and shocked. Was that an actual Pep failure or were there other factors involved? Thanks again!!

  12. Dr. i had sex with a friend on friday 11pm nigeria time. then on Monday she got tested for hiv and she is positive. my point here is that i got exposed to hiv infection. i want to know if starting the PEP at about 68hrs from exposure makes me on safe?

  13. Hi Doc

    Thanks for responding to so many people on your site. Please try and andvise me. I was on PEP and took the last pill two weeks ago.

    I am still experiencing a very dizzy and drowzy “cloudy” feeling everyday which I believe is a symptom of the tablets and the toxic effect its had on me.

    Today I received my negative HIV result from the lab 6 weeks post exposure.

    I’m really scared this feeling wont go away, it feels very very strange and is making me feel fatigued and its effecting my work, mood and lifestyle.

    I would appreciate and advice on what to do going forward.


    Thank you very much in advance.

    • I really cannot diagnose you over the internet. I cannot tell if your symptoms are due to the PEP meds or something completely unrelated. You should go back to the doctor who prescribed you the PEP.

  14. Need meds

    Hi Doc

    I am currently on the generic Teevir therapy and I have my prescription as ordered by my doctor. However, I need contact(s) for local supplier since I am not able to travel to Bangkok to get it.

    As such, I’d like to check if you have contacts for any local supplier?

    Thank you.

    • That is a prescription only medicine in Singapore. You will have to visit a doctor to get a prescription. You can then purchase it from the doctor if he has it or purchase it from a pharmacy with the prescription.

  15. Worried

    Dear Drs,

    There was unprotected insertive oral sex, and the frenulum tore with bleeding. No cuts, sores or ulcers in her mouth.

    Would you recommend PEP?

    • I cannot make medical recommendations over the internet. Please see your doctor. You are very welcome to visit any one of our clinics. Click HERE for location info.

      • Khan Aminur

        Hi doctor, I am hiv positive.sometimes my arms and nick burning. Sir any primary treatment?

        • You may be suffering from HIV associated neuropathy. There are medicines to control this. Please see your HIV specialist for more advice.

  16. Hi Doctor,

    I had unprotected sex last year, but was unsure if there was any exposure and if my partner was positive or negative. I started on PEP within 72 hours and finished the entire course. Went for a checkup at the end of the course (5 weeks after the incident) and tested negative. I have not gone back for a test since then. A few days after starting on the PEP course, I developed symptoms of a cold which later turned into a sinus infection. I’ve been taking medication for the past few months because of the sudden sinusitis. Is it possible that my sinusitis development was a sign of seroconversion, or is this likely due to other factors?

    • That is an impossible question to answer. What I do know is that your HIV test at 5 weeks post exposure, although very indicative, is not 100% accurate.

      • Hi Doctor,

        Thanks for your response. I will be going back for a test to confirm. So far, have you seen any cases of the test results changing after a test at 5 weeks?

  17. I am currently undergoing PEP treatment following a very low risk exposure. At 11 days, I was tested for HIV by the RNA Qualitative Test. My question is, would my use of PEP affect the results of the RNA test, which tests for the presence of the virus.

    • Unlikely. However, RNA test is not the gold standard for HIV screening. I suggest you get a HIV antibody/antigen test 28 days from exposure.

  18. I received an unprotected oral sex from a Filipino girl working in a pub at boat key. We have wet kiss which i understand is less risky.
    Please help me to guide if I need to be in any sort of medication or PEP this happen on Friday night. We did not have vaginal or anal sex. I am still under 72 hours period.

    • drtan

      Click HERE for more info on the risk of HIV from oral sex. We cannot determine if you need PEP or not over the internet. That is amounting to giving medical advice which we cannot do. You are welcome to visit any of our clinics. Click HERE for location info.

  19. Dear Doctors,

    I had a sexual intercourse with a CSW in Geylang (legal house with a number in front). I used a condom during the intercourse. Prior to using a condom, the lady was sitting atop me using her hand on my penis, but her vaginal fluid might touch my scrotum. The lady also performed a protected oral sex to me.

    Can you please help assess my risk of attracting HIV from this encounter?

    I also read from your article that it was many years ago that MoH found a HIV positive case among legal Geylang CSWs and not any in recent years. Is this information still up to date?

    Thank you very much doctors.

    • Lastly, does this incident warrant a PEP treatment in your view? Thanks very much for your opinion doctors.

      • drtan

        We cannot tell you if you need PEP or not. That amounts to giving medical advice over the internet which we cannot do.

    • drtan

      The risk of getting HIV from protected sex is extremely low. The chance of the CSW having HIV in the first place is also extremely low. Legal CSWs are required to attend monthly HIV tests to retain their license.

  20. Dear Doctor,

    I went to a well know massage parlour in Thailand. The masseur used Johnson baby oil to massage and did a handjob for 1-2 minutes. After which she put on the condom and we had intercourse. There is no obvious breakage Nor slipped off. The contents were contained at the tip of the condom. I saw from numerous website that baby oil will breakdown the condom but gives me a big headache if I should immediately seek medical attention based on this encounter? Please kindly advise what should be my next step? Thank you so much doctor!

    Best Rgds


    • Your next step should be to see a doctor and get tested for HIV and all STDs. Condoms (even without baby oil) are not 100% effective. Condoms reduce the risk of HIV significantly but not 100%. Condoms reduce the risk of other STDs but also not 100%.

  21. Helo DR,after 18 days exposure and i make cmia ag/ab testing and rsult was negative…it that accurate??how about your opinion Dr?

  22. Terence

    Dear Doctor,

    I started PEP (Raltegravir and Tenvir EM) at about 45 hours, am I still at a high chance of not getting infected (condom breakage MSM, I am the insertive partner)? I heard the chances of failing here is quite high after 36 hours. Do clarify!

    • Well honestly this question should have been answered by the doctor BEFORE giving you PEP. You really need to know what you are getting into ESPECIALLY the pros and cons of taking medicines BEFORE you take the medicines. So now if I tell you the chance is still high are you going to stop the medicines? That ship has sailed man.

      For what it’s worth – No I do not think the chance of failure post 36 hours is high. There is also no data to back up that statement.

  23. Hi Dr Tan
    I was contacted herpes on early October last year. Although I do not have physical ulcer and I have paid sex with a masseuse just last night. Will I still get hiv through skin contact though I have sex with condom. Kindly advised whether the risk is there?

    • I am assuming you had a Herpes outbreak in October last year. And you are now worried that the fact you have herpes increased your risk of getting HIV from your exposure last night. But you are unsure how much it has increased your risk because you are not having an active outbreak. The fact is, having a herpes infection increases your risk of getting HIV. You can read up more in my article HERE. You have also made the erroneous conclusion that condoms are 100% safe. They are NOT. In fact, there is more evidence of getting HIV from protected sex than there is of getting HIV via skin contact, herpes not withstanding.

  24. Doctor,
    How good is a test at the end of PEP , the next day after last day of PEP ?
    Many online forums say the window period starts after the last day of PEP. How true is this ?
    Does PEP affect the presence of p24 antigen ?


  25. Dear Dr tan
    I had unprotected sex with lady one time only before 22 months back and it is first and last in my life.my symptoms are body pains,weight loss 4kg in 22 Mon,sore throat don’t go away.This sore throat problem is also in that lady.I checked my HIV status HIV Elisa 180 and 360 days negative, SD bioline HIV 1/2 3.0 antibody after 560 days negative and recently test HIV 1/2 antibody+p24 ag combo test at Dr lal pathlabs which is most famous lab in India is also Negative (0.05)/1 at 21 months.sir please tell me what risk behind it if it negative.
    If you say to correct suggestion to me becage I get marry soon sir.please give your valuable information to me.

    • I get many questions like yours and the thing that really baffles me is why do you not trust your tests? You have tested so many times in what you say is the “most famous lab in India” and yet you are still concerned about being infected with HIV? The only logical reason for you to be still worried is that you think ALL the tests you have done in the “most famous lab in India” are WRONG. Does that make sense to you? Can they really all be wrong? If you have reason to believe this is the case then please go get tested at a different facility. If not, why are you still worried? It just does not make sense to me.

  26. Hi Doctor,
    I had a Protected Vaginal Sex with a sex worker and was not sure if there was any break in the condom (It was intact) So went on PEP after 42 hours.

    Would a 4th Gen test result at the end of PEP ( 28 days ) be conclusive ?

    Thank you.

    • I am unable to control the fear and Anxiety.. Also Have you seen any case of PEP failure with (Truvada + Isentress) ?

      • Yes, it would be conclusive. However, we would advise you to repeat another HIV test after 3 months just to be on the safe side.
        PEP failure is possible.

        • Thanks for the Response Dr Sii.

          Have you Personally witnessed Pep Failure of Truvada + Isentress ?


        • Dr ,
          One Last question.. Have you seen cases of Infection when there was no slip or break in the condom ?

          Thanks for all the info.

  27. hatinggeylang

    Hi doctor,
    How could we realize that a girl seated in a legal brothel in Geylang does not have HIV?
    I mean however it is said that they have to check up monthly, what could assure that the brothel’s owner does not fake? Who is going through the brothels one by one to check all of the girls’ licenses? And also what assures that a girl performs the blood experiment once a month?
    Thanks a lot.

  28. Hi doctor!
    I’m from Brazil and I nad unprotected insertive anal sex with a sex worker. It was on december 18h, and started PEP about 10 hours after. I took tenofovir/lamivudina, atazanavir and ritonavir for 28 days and did a rapid test (bioeasy), immediately after PEP, which came negative. Which is my risk of seroconvertion now?
    Thank you

  29. hi doctor tan,

    i performed oral sex on prostitute and realised that there is pimple around my mouth may be burst while performing cunnilingus. is my chance of getting hiv high? do u think i should get pep? thanks

  30. iamsostresss

    Hi doctor I have sex with a sex worker on sunday 10 january with a condom and I didnt ejacualate and there were no signs of body fluids from her. I ejacualated when she was giving me a handjob and later she give me a blow job without a condom. After that I went drinking and I drank abit too much and the next few days I am having a hangover with rapid heart beat dizziness and I realise today I have red little dots on my back and I am getting abit of paranoid. Up till now my heart still beat very fast probably becos of the hangover which last for 4 days already.
    1.i want to ask about the pep do you recommend me to take it because recommended is 72 hours but in my case is about 100 hours since exposure…
    2. And is the small little red dots on my back a early sign of hiv? I am getting worried
    and anxious.
    3. what do u recommend I do I am feeling lost and depressed.

  31. iamsostresss

    Hi doctor I have sex with a sex worker on sunday 10 january with a condom and I didnt ejacualate and there were no signs of body fluids from her. I ejacualated when she was giving me a handjob and later she give me a blow job without a condom. After that I went drinking and I drank abit too much and the next few days I am having a hangover with rapid heart beat dizziness and I realise today I have red little dots on my back and I am getting abit of paranoid. Up till now my heart still beat very fast probably becos of the hangover which last for 4 days already.
    1.i want to ask about the pep do you recommend me to take it because recommended is 72 hours but in my case is about 100 hours since exposure.
    2. And is the small little red dots on my back a early sign of hiv? I am getting worried
    and anxious.
    3. what do u recommend I do I am feeling lost and depressed.

  32. Richard

    Dear doc,
    I Had protected oral and vaginal sex with a sex worker. Used new condom after each sex act. However, after a short period of penetrative sex, I noticed that she was bleeding in her vagina. Washed up quickly soon after.
    Her blood may have come into contact with a pin prick on my finger I got in the morning at work. I am uncircumcised, and am not sure if the condom broke or not. Please advise me if i am high risk and if PEP is required? Thank you.

  33. Hi Doctor,
    Just a side question. Are there any historical cases of unethical practice in Singapore, like doctors intentionally use “dirty needles” on patients?
    Like ya know, wala on infected already then seek my treatment! Something like that ever happened?
    If not, how does HSA ever keep these scandals in check?

  34. Hi doc, I realized that my partner and I forgot to use the condom during sex, and he had recurring fever and ulcers recently. Is it recommended that I take PEP as I am not sure if he is HIV positive or negative. It’s still less than 72 hours after exposure.

    • Hi, if you are unsure if he is HIV positive or negative and you had unprotected sex and its still within 72 hours, then I would advise that you see a doctor as soon as you can to further go through your risk and decide on PEP treatment. You are welcome to visit us at any of our clinics.

  35. Hello doctor i am on pep with isentress and truvada from one of your clinic
    I dont have high fever but i feel really cold sometimes, tired and little bit muscle ache
    R these common sides effects or sign of seroconversion..its my 8th day after exposure

    • Dr Justin Sim

      These symptoms are likely due to something else such as a common virus. Give it a few days and see.

  36. dear doctor I had sex with a sex worker from a brothel in geylang, i used the condom but it slipped of after my boner gone after i ejaculated, i am not sure if the condom slipped off while she was on me or after she withdraw on me. but I think i didnt penetrate her because my boner was gone..she was keeping jumping on me for afew minutes. what is the risks of hiv and i started taking pep in 36hours

    • Can i also know the side effects of pep..i feel tired, weak and cold. I am scared doctor

      • Hi doctor,
        I had a massage 5 days ago and the masseur offer me extra service. We ended up having anal sex (me insertive). After 5 mins i remove my penis because i could not get a good erection just then i noticed the condom was broken. He finished me off with a hand job. I showered straight away. Started on PEP 25 hours after (tenofovir and efavirenz). He is hiv (+) and not on medications. What are my chances of testing negative of hiv with pep? Should i worry?

        • If he is on HIV medication and his condition is under good control, your chances of getting infected with HIV are low given that you have started yourself on PEP in 25 hours from exposure. The best thing to do is to complete your PEP and get yourself tested.

  37. Worried About Massage SA

    Hi Doctor

    About 10 days ago I had the following incident.

    I was given a massage by a prostitute in South Africa. While she was massaging I am worried that her vaginal juices (mixed with massage oil) came into contact with either my anus or small ruptures in the skin outside of my anus as she was rubbing quite a lot with a vagina.

    I then proceeded to have a blow job from her (with a condom on)

    I then proceeded to have sex with her (also with a condom on).

    I have not developed any symptoms like the flu or rash. However, this morning I noticed a wart on my big toe.

    I took Atripla for PEP 4 hours later .

    I have the following questions

    1) What is my risk of HIV infection

    2) Should I continue PEP

    3) Is the wart an indication that I have been infected with HIV

    4) Is a wart a sysmptom of acute HIV

    Thank you

    • Worried About Massage SA

      I understand that even correctly used condoms carry some risk of HIV transmission. When I ask about my risk I am specifically asking about risk of transmission from the massage as I described it

    • Dr Justin Sim

      1) Incredibly low. Almost certainly not going to contract HIV this way.
      2) Since you have started you can continue but this is up to you. It is not really necessary in this case.
      3) Warts on your toes are not signs of HIV.
      4) No

  38. Hi Doc,

    Would like to enquire regarding to my situation.
    On 1 Oct, I have massage and have sex with a girl. From the begin, I was receiving Oral sex from the girl before that she is using oral B in her mouth and did oral sex without any condom to me. After that again oral sex without Oral B but no ejaculation at all. After we went to have sex with condom and ejaculation into her with condom on and on sign of breakoff. I am very worried and make me crazy on thinking about getting any diease and i felt regretted and was my first time. Please kindly assist. Thanks

    • No sign of break off

    • Dr Justin Sim

      The oral B will not protect you against STDs so you should still get testing for that. This is the only way you can be sure.

      • Hi Doc,
        What are the test which i need to test for and what is the windows period?

  39. anxiety

    hi dr,

    just wondering I am currently taking PEP.. and I was informed by doc that it cause nausa and diahhore

    does PEP delay seroconversion? if it does not work?

    and are test taken after PEP finish be accurate?

  40. Hi doc
    I have in touched with hiv positive girl then i am abit late taking pep at 76 hours and during taking i went to have blood testing (pcr viral load) at 11 days and 26!days after touching, the result is under detected.is it effective for me of late taking pep? Is this the conclusive result for me or when do i need to retest it for the coclusive result? Best regard

    • There are no studies to validate the efficacy of PEP after 72 hours from exposure. So there is no way for me to comment on whether the PEP is effective for you. Also, all guidelines on PEP recommend retesting for HIV 3 months (sometimes 6 months from exposure). Click HERE for more info.

  41. Stupidguy

    Dear Doc

    Sorry for my English.I gave an unprotected cunnilingus and protected sex with sex worker in my Thailand in 11th August. I decided to took a Pep around 36hours after exposure. Thai’s doctor gave me Truvada and Edurant.for 28 days. I get tested after finished Pep immediately with 4th generation and NAAT. It all negative. Do you think this result is how many percent trustable? Do I need to test again at 1 month and 2 month after Pep? I’m gonna be crazy please help me.


  42. Dear Dr tan,

    One guy cunnilingused me for about 5mins, and made me cum.I have not any cut or wounds.He did not have either as he said.He is not a gay,but have sexed with some partners(not hooker),I did not know him very well of the rest.
    I bought PEP in your clinic,and already passed 10days.I feeling not good about the PEP,because it made me easy to get tired and brown skin color…I need to know:

    1.Are there many cases get infected with HIV just through be cunnilingused?
    2.I am worried about the PEP’s permanent harm to liver and kidney.I was very healthy of liver and kidney.
    3.I know I can have test when reach 28days.But when will I 100%safe? 3months?6months?28dyas is 90%accuracy?
    4.Maybe I take PEP is more harm than good,need I continue?

    Thank you so much.

    • 1) Risk of HIV transmission via cunnilingus is very low. So far we have not come across anyone who got infected that way. A few case reports around the world are limited to people performing cunnilingus rather than receiving it.
      2) Chances of PEP harming your kidneys and liver are very low. We have not seen it so far. But we ought to check it because there is a theoretical risk.
      3) Test at 28 days is already conclusive enough. However, we will repeat it at 3 months just to be on the safe side.
      4) If you have already started taking it, I suggest you finish the course, unless the side effects are not tolerable at all.

  43. worried6789

    Hi doc Tan, I am writing with tears in my eyes. Please give me some advice. My condom broke while having vaginal sex with a girl a month ago, i found out in seconds and wash my penis with soap and water immediately…i found out the condom break in seconds after it break… i get her tested the next morning and found out she had HIV… i started Combivir 16 hrs after exposure and to get the other component of the PEP(ALLUVIA) 60 hrs after exposure. i however took the PEP as priscribed. 2 weeks after exposure i started to feel lower groin pains, it went away for a while…it was non tender and i didnt see any enlargement of the nodes, the area was just painful….2 weeks later the pain started again in the groin area.. which is nontender, aggravated by bending over. i also have pain in my legs and scrotal area, howwer these places are nontender. i exhauseted all the different antibiotica with my doctor and no improvement. i think i feel a little pain behind my ears and armpit but unsure, the nodes there are not enlarged…DO U think its the HIV causing this? i have no sorethroat, fever, headache, rash, etc..HELP !!!!!!!!!

  44. Dear doc
    I had sex with prostitute girl on the 5th september 2015. During that time my condom broke, then i had rushed washing. After that i checked for elisa (hiv )that girl is hiv positive. Then i started taking PEP 8 days then i went blood testing hiv(cpr test viral load)the result is negative. Is the result conclusive for me. Should i stop taking PEP?
    Best regard Doctor

    • Dr Justin Sim

      No continue taking your PEP. It is possible that the PEP has created a false negative situation. You should finish the course and then get retested at the end.

      • So, is it conclusive testing after i finish 30days of taking PEP. No need to wait one month after completing PEP then testing or when i should wait for the coclusive testing doc? Best regard

        • Dear doctor
          I take PEP maybe 75 hours after my condom broke with hiv positive girl Then after 8 days of taking PeP and the total days of contacting was 11 days,i went to test pcr (virus load) and the result is undertected . So when will i go to have blood testing for the conclusive for me? And does PEP affect my result of undetected?
          Best regard


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