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.
Hi Jack, at 35 days post PEP this result will be more than 95% accurate. To be 100% sure a second 4th generation test is required at 42 days. As you have tested negative it remains very likely that you are HIV negative but to confirm your result you will need this second test.
Hi
I am jack, i have a 4th generation test on the 35th days after i take PEP, it come out negative, my DR said is conclusive enough, but here i know that after 6weeks means 42 days after PEP only conclusive, so do i need to test again with 4th generation? Please help, i am suffering anxiety and anxious now
Hi Franz, this is very low risk. In the UK PEP would not be recommended. Oral sex carries little to no risk (there has never been a documented case of transmission via oral sex). As there was only penetrative sex for a short moment this reduces risk further. As you have mentioned, she is much more likely to be negative. While starting PEP within 48 hours is recommended, it is suitable to start within 72 hours.
Please follow this link for more information: https://i-base.info/qa/factsheets/hiv-transmission-and-testing
Hi, I’m freaking out and would like some advice.
I had a drunk hookup with a girl I did not know. We didn’t have any condoms so I told her oral only. At one point though she slipped my penis into her vagina. I pulled out and then got up and washed with soap and water. We finished with more oral only.
I got freaked out. She is not particularly likely to have HIV and reported her exams are clean and she is on iud contraception. She is highly educated and a professional and seemingly responsible.
I went to a clinic within hours and received a PEP prescription of Tivicay and Truvada. However due to insurance problems I had to fill it at a specialty pharmacy and could not get the medications until 53 hours post exposure. I am freaked out because everything I read says after 48 hours it’s less effective.
How would you assess my risk??
Hi Anonymous, if by protected sex you mean you used a condom, there is no risk of transmission. Please follow this link for more information: https://i-base.info/qa/factsheets/hiv-transmission-and-testing
As for your current symptoms, you have mentioned the likely reasons e.g., your brother being ill and you living with him, or you having period-flu, or the stress that you have mentioned. HIV is not the cause of your current symptoms.
Hi,
I had protected sex (we were drunk), it was quick penetration and I asked him to stop as I was too tired. No orgasm or ejaculation. I found out the guy might be HIV positive the morning, someone told me. I confronted him immediately asking him to be honest and he was telling me no. We spoke for 30 minutes and he kept telling me he wasn’t.
I was far out of town or close to a doctor or clinic. I had a video call session with my doctor as my nerves were on end. She sent me my prescription to go PEP, but I could only get the meds 55 hours later as I was far away.
I got the meds took everything, started the 30 day application. I went to see my doctor had all tests done and everything came back clear.
I’m currently on day 24 coming close to the end of my meds.
Now, my brother came back from his holiday and he was sick with the cold/flu. I’m starting to cough now and have a blocked nose.
Im concerned now as I don’t know if he infected me with his cold (we live together) or my hormones are raging as I’m having my period soon and I usually get period-flu before my monthly’s or that I have been so stressed out. I haven’t had a good nights rest ever since.
What do you think my chances of being HIV positive is seeing my given situation?
I have another doctors appointment soon just do more blood test and see if I have any other infections and then my 6 week test will be done at the end of the month.
My doctor said she thinks I’m fine, but I’m freaking out here and see that my brothers cold was contagious I want to know how this is going to affect me now.
I just feel nauseous and have headaches because of the meds, but now have an irritating throat and runny nose. Please help.
Hi Treasure, Reydin is enough. Reydin is a combination pill that includes 3 drugs. It is very commonly used as PEP. You do not need to be taking the multivitamin/mineral as well. Depending on what is in it, it can sometimes reduce how well Reydin works (this can be avoided by taking them at different times of the day). There is no evidence to suggest taking a multivitamin alongisde PEP will boost how effective PEP is. Reydin alone is suitable.
Hi Doctor, my name is Treausure. I just had unprotected sex with a lady I know. We decided to test 30min after, my results were negative and hers were positive. We were both shocked, more especially her. I went to see a doctor immediately, and I was put on Reydin to take once a day, I took the first one 30min or an hour, factoring time at the doctors. The lady at the pharmacy recommended I get Activovite which is a multivitamin and mineral. It was not on the original prescription from the doctor so I’m wondering if that will not impact the effectiveness of Reydin. Do you think I should continue taking them both. Please I’m so scared. I see people are saying they taking 2 so now I’m not sure if just taking Raydin is enough or I should take more in terms of something else along with Reydin. Thank you
Hi Stella, as you started PEP within 48 hours your treatment will be effective. Do you know if this person was on treatment or if you used a condom? Both of these can prevent transmission.
Hi…I started my pep before 48hrs now am really stressed because I knew the person is Positive should I not worry coz am taking them just on tym