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. Simon Collins •

    Hi Ap,. as with last time, please talk to a doctor about if the risk needs PEP. We can give this advice. In the UK though, anyone who uses PEP has a discussion about using PrEP instead in the future.

  2. Ap •

    I had unprotected sex last month, yesterday condom failed. Should I take PEP as last time I already had unprotected sex. I’m not sure if my partner is positive. I don’t have any symptoms

  3. Simon Collins •

    Hi Hubert, this guide has everything you need to know about PrEP.
    https://i-base.info/uk-guide-to-prep-february-2024/

    In the UK, F/TAF (Descovy) and F/TDF (Truvada) can both be used. They can also both be dose the same way.

    However, they are different drugs and can’t be used at the same time. Using one ofr a while is fine and switching to another is ok later.

  4. Hubert •

    Hi, Thank you for your watching. I used to live in Malaysia before, and at the beginning of July, I come to China for working. And When I am in Malaysia, I take the prep of Descovy for daily dose until 7.14, but I found that I can only get the prep of Truvada here in China, so I have taken the prep Truvada since 7.14,But I had unprotected sex on 9th, July, and it was not reach the day of the last 7 days before ending the prep of Descovy. And a Chinese doctor told me that the drug ingredients of Truvada and Descovy is same, but I have no idea about the blood drug concentration if it is enough to protect me?

  5. Josh Peasegood •

    Hi Missy, do you know your partners viral load? If he has a viral load below 200 you do not need to be on treatment.

    His own treatment suppressing his viral load will be enough to prevent transmission. This is explained by U=U: https://i-base.info/u-equals-u/

    If you are still concerned you can use treatment to prevent transmission (if his viral load is above 200). Treatment will not be harmful to baby and will not prevent pregnancy.

    Reydin is usually used as treatment or PEP. To prevent transmission before exposure you can use PrEP instead. This is similar to Reydin but used fewer drugs and is more effective.

    PrEP: https://i-base.info/guides/prep

  6. Missy •

    Hi , my partner is HIV positive but he has been taking ARV for little over a year. We decided that I would see a professional less then 10 hours later after we had unprotected sex for the first time. Since I have been on Reydin, that I have to take for 30days. While I have been on this medication, we have been trying to have a baby, meaning unprotected sex ,while he is faithfully on his treatment and me on the Reydin. I have to return after 30 days to get tested. Are we on the right track in terms of making sure that I remain negative same time trying to get pregnant? Please help!

  7. Josh Peasegood •

    Hi Christy, please see here for information about transmission: https://i-base.info/qa/factsheets/hiv-transmission-and-testing

  8. Christy •

    I had unprotected sex not knowing his HIV positive around January and again around February but I found out after my third sex on 23 February and I enroll on TLD(PEP) within 20hours of exposure

  9. Josh Peasegood •

    Hi Adjoa, it is great to hear your husband is now on antiretroviral treatment. When were you last tested yourself?

    After 3 months most people will have an undetectable viral load. This means they have a viral load below 200. When this happens and they are on treatment it is impossible to pass on HIV via sex. This would protect you from transmission. As you have only been having unprotected sex in the last 2 months, your husband would have likely already had a suppressed viral load preventing transmission.

    This is called U=U: https://i-base.info/u-equals-u/

  10. Adjoa •

    My husband is on antiretrovira drug for six months and some weeks now ,for two months now we’ve been having unprotected sex so am scared I will contract the virus