Question

How often can one use PEP for unprotected sex?

28 November 2022. Related: All topics, HIV transmission, PEP/PEPSE.

How often can one use PEP (AZT with 3TC) for unprotected sex?

I have done this three times now (about six months in-between) with my partner as sometimes it is difficult to use a condom and I am afraid to insist that he gets a test done.

So far, I have tested negative.

Will this result in me being resistant to the drugs in future?

Answer

Answer: Simon Collins

Hi there

Rather than keep needing PEP, most people would talk to their doctor bout using PrEP instead.

This would be much less stressful and would protect your health better.

Please see the link for more information about PrEP:
https://i-base.info/guides/prep

Please see this link for more information about PEP:
https://i-base.info/qa/factsheets/pep-faq

best wishes

Note: This question from 2008 was updated in 2022.

70 comments

  1. Josh Peasegood •

    Hi Regina, no you do not need to extend the course of your PEP. As you still have more than 2 doses remaining, your current treatment will work like PrEP. This means you are protected from further exposures while on the course.

    You can finish the course when originally planned in 6 days.

  2. Regina •

    Its my 22nd day on pep only 6days remaining for 28days… i had unprotected sex today.. though have not tested my patner and he has no problem in testing… should continue with pep even after 28day…kindly advice

  3. Josh Peasegood •

    Hi John, while on PEP it is recommended to either not have sex or to use a condom. This is because you are unaware of your status and there can be some risk of transmission even though small.

    For more information please see here: https://i-base.info/qa/factsheets/pep-faq

  4. John •

    Hi, someone who takes PEP and has started within 24hrs of exposure; He has tested negative to HIV, but because he was exposed to, he is afraid of conjugal rites with his wife that he can risk her to HIV. Please advise him whether he can continue sexing with his wife or until he finishes the dose?

  5. Josh Peasegood •

    Hi Muzo, while on PEP you are protected from further exposures. You can finish the course of PEP when originally planned. You do not need to increase the dose?

    What is your husbands viral load? If it is below 200 there is no risk of transmission even if it is detectable. Even when higher than 200, being on treatment should mean his viral load is suppressed enough that the risk is minimal. When the risk is small sometimes it is not even recommended to have a course of PEP.

  6. Muzo •

    Am HIV negative my husband is HIV postive and is on TLD for 1 year now , but still have detectable Viral road I had unprotected sex with him and I started pep I was given TLD for pep after taking for 7 days I hand another unprotected sex with him, can i continue with pep or what should I do am I at a more high risk, should I increase the dose.what should I do.

  7. Josh Peasegood •

    Hi Tim C, using repeated courses of PEP is not going to reduce how effective it is. As you had an exposure the following day from PEP, you only need to continue with PEP for 2 days after sex. In this case PEP would work like on-demand PrEP.

    Have you considered using PrEP? It is a medication similar to PEP but it uses fewer drugs. It is used before exposure instead of after and is much more effective at preventing transmission.

  8. Tim c •

    I have just finished my last pep on 4/13.
    And I had another exposed on 5/13 morrning, I restart the pep in same day afternoon and also tested negative,
    It’s my 3rd time pep this year, I know I’m stupid, but will so many use make the pill lose effectiveness?
    I only have BJ last time (mostly with common, about 10sec without condom)
    But this time I was drunk. I can’t remember will if I have protection in whole time.
    Please help me. I don’t experience any side effect that’s why I keep using it.

  9. Josh Peasegood •

    Hi Kudzai, PEP will still be effective. The effectiveness of PEP is not reduced by using it more often. Have you considered using PrEP? As you have had repeat exposures in the last year, PrEP may be more suitable at preventing HIV prior to exposure rather than relying on PEP after the exposure. More information can be found here: https://i-base.info/guides/prep

  10. Kudzai •

    I have been using PEP for 4 months in a year i recently git exposed again to HIV…will PEP be effective this time as i have taken too much already