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.
Hlo sir, my name is rahul. I had unprotected sex with a guy on 26 may 2019 but I don’t know his hiv status. After sex I warry about hiv. I consult the doctor and he suggested pep drug( Emtricitabine & tenofovir, and Darunavir and Ritonavir). These medicine i start on 28 may 2019. I finished these medicine on 26 June 2019.
On the 3 july 2019 I go for hiv test and the test result is nonreactive .
After one week I feel a neck infection like sore throat than on the 16 july I go for another hiv screening test and the test results is nonreactive.
My question is what about my hiv status.
Hi Rahul,
Some HIV tests give an index number as a result. If the number on your test is less that 1.0 it means you are HIV negative. So long as it is below 1.0 the number itself has little meaning
Please see this Q&A for more info.
Hlo sir, my name is rahul. I had unprotected sex with a guy but I don’t know his hiv status. After sex I warry about hiv. I consult the doctor and he suggested pep drug( Emtricitabine & tenofovir, and Darunavir and Ritonavir) . I finished the medicine then after one week I go p24 combo test and my result is – index value is 0.07 and nonreactive . After 15 days I go the second test that time my test result is 0.13 and nonreactive.
My question is the increasing the index value is show the hiv positive if not than why the index value is increasing.
Hi Jay J,
It’s not easy to answer this question.
But many people are now surviving well on HIV treatment (ART). That’s because modern ART is safe and effective.
I slept with an HIV positive person… she assured me she was negative but she was hesitant to go with me for an HIV test. 2days(48hrs)later i drove her to a clinic where we were tested and her results were positive and i was negative i rushed to a hospital and got PEP which I swallowed after 52hours after exposure.. How effective will it be and what are my chances of surviving the virus???
Hi William,
A 4th generation test will test for antibody as well as antigen. Please see here for the window periods for an HIV antibody positive result.
Hello,
I am very worried on all what i read of testing after PEP.
I am living in Kenya and the Aga Khan university hospital is recommending after PEP treatment of 28 days you can test with a 4th generation elisa lab test and its very reliable.
On the result form is been written as follow:
Negative, (0.194)
The current used fourth generation immunoassay measures IgG and IgM Ab to hiv-1 and 2 as well p24 antigen and has a specificity of 99.7%. Sensitivity is nearly 100% after a window period of about 2-3 weeks after infection.
While other websites are stating: test 4 weeks after test is completed and then is 95% sure.
Some Europe countries are testing after 6 weeks.
The doctor advised me that i need to do a confirmation test after 3 months. But because of the very sensitive test, I don’t need to worry at all.
The hospital is sanas m0493 certified and its accredited by Joint Commission International, USA.
So, what is true?
Many thanks in advance,
William
Hi Karen,
Please see this Q&A for symptoms of seroconversion for HIV. That means converting from HIV antibody negative to HIV antibody positive.
Taking PEP can delay HIV infection so that’s why you’ve been told to test a month after your last PEP dose.
But you can ask for a test as soon as you finish PEP if you want. Then you can test again a month later.
Hello, im a 27 year old female and had sex 2 weeks ago with a man and the condom broke and he came inside me. I asked if he’s ever been tested and to my dismay, he said never ( that he had never had any reason to). I went to the clinic the next day and began PEP treatment Truvada and Tivicay for 30 days (22 hours after the condom broke). I am now on day 14 and woke up with a sore throat. Exatly 2 weeks after possible exposure I’m experincing sore throat and general ill feeling, could i be experiencing hiv symptoms?? I was told to come in and retest as soon as my 30 day PEP treatment is done. This seems to early. Should i come in a month after my last dose of PEP is taken insted?
Hi Kit,
if you’ve tested negative after 4 weeks this means that you’re negative.