Question
Is PEP effective if taken 48 hours after exposure?
2 July 2021. Related: All topics, PEP/PEPSE.
I paid for sex with a woman but the condom tore and I only realised after I was done. There is a high chance that she was HIV positive. I started PEP after 48 hours.
I got a PCR test done 17 days after exposure. It had a less than 20/ml (undetectable) result.
Now between 14 and 35 days after exposure I have had signs of thrush, mild red rash on my face and a couple elsewhere. But no fever or swollen lymph glands.
Can the rash and thrush be because of utter stress and obsession?
My doctor says that the PCR can be relied upon and that I am negative.
Can the PEP have reduced the viral load to less than 20/ml as I took it for 15 days before the PCR test?
Please give your expert advice. I am very anxious. Thank you.
Answer
Thank you for your question.
The risk of HIV from one broken condom is very low. If your partner had an undetectable viral load on treatment, then the risk would be zero. If they were not on treatment the risk might still be only 1 in 300 or lower.
You cannot guess someones HIV status so your assumptions might also be wrong.
You started PEP within 48 hours, so it is likely it will work.
PEP – stands for Post-Exposure Prophylaxis. It is a term used for taking HIV drugs to reduce the risk of infection. PEP usually involves taking a combination of three HIV drugs for one month. The earlier PEP is started, the more likely it will work. Ideally, this should be within a couple of hours. If this is not possible, then still the earlier the better.
Some guidelines include a two-day window to do this (i.e. within 48 hours). After this, effectiveness is much less likely. Other guidelines allow up to 3 days (i.e. within 72 hours). Sometimes this may be more for psychological benefit. For example, if someone is very stressed or traumatised.
No guidelines recommend starting PEP after 72 hours.
After finishing PEP you need to wait a 4-6 weeks before testing.
If the PEP has worked, or the person was not initially infected, this will show as a negative HIV test. The test you did 17 days after the exposure will not be accurate yet.
If the PEP has not worked, this will be shown in a positive test result. Testing 4 weeks after PEP will detect 95% of infections. Testing after six weeks will detect more than 99% of infections. This result doesn’t need to be tested again.
If PEP has not worked, serosonversion usually occurs 1-3 weeks after PEP is finished. However, only 80% of people show symptoms.
Please test 6 weeks after you finished PEP is finished. If you test any earlier, you need to take a second test 3 months later.
Viral load (PRC) tests are not approved to test for HIV. In some cases they can have a role.
Please see a doctor to talk about your symptoms he best way to confirm what is causing them is to see your doctor. He/she will be able to diagnose and treat the symptoms accordingly.
Please see this link for more information about PEP:
https://i-base.info/qa/factsheets/pep-faq
Note: This answer was last updated in July 2021 from an original post from December 2011.
Afternoon doctor, i take pep for 28days n I went lab on next Month n am negative n nw i went for six month nw am negative i hope am Free nw
Hi Druza,
Unfortunately we don’t have resources to answer questions on HIV testing and transmission. But here’s a link to the FAQs about this.
good day
i had sex with a condom with some lady however i didn’t realise that i had a pimple witha small wound next to my penis and it seems like her body fluid touched it, what are the chances that i might be infected if she has HIV which she claims not to have?
Hi Mlungisi, If you tested HIV negative a month after finshing PEP it sounds like it worked. But you can talk to the doctor about your HIV test if you think it was a false result for some reason.
hie. i slept with someone hiv positive . the condom broke and she was bleeding . i immediately went for pep and the doctor prescribed med for a month . is it possible tht im hiv positive ? after a month i tested negative but im not sure if im safe
Hi Dany,
We don’t have resources to answer questions about risk and transmission. But all frequently asked questions about this are answered here. Questions about PEP are answered above.
hello sir / mam
I paid for sex with a woman without condom and I only realised after I was done. There is a high chance that she was HIV positive.
so kindly suggest me what can i do and how i prevent me about hiv virus spread in my body
dear manual I would advice you to go the doctor and start the pep. I was in a similar situation last month I didn’t know the guy status so I didn’t want to take chance went to the doctor antiviral prescription I just finished the treatment it’s better to be safe than sorry
Good Day Manuel,
Unfortunately i-Base doesn’t have resources to answer questions about transmission and testing. However, all frequently asked question are answered here.
If you think you have been at risk you should go to the clinic and discuss PEP with them.
Good Day,
I had unprotected Sex with a Lady on 12th August 2018 – We didnt plan it, it just happened. I’m currenlt HIV Negative as at 13th August 2018 when I did the Test. I do not know her status and she won;t go for a Test. Do U think i should start PEP. kindly Advice before the 72hrs Windows runs out.