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.
Note: This answer was last updated in July 2021 from an original post from December 2011.
Hi A, a 4th generation test is only conclusive from 6 weeks after the last dose of PEP.
Hi Mr.josh, 5days after my end of PEP.
Hi A, how many days has it been since your last dose of PEP?
Hi mr.josh, I already met with my doctor yesterday and he tested me with 4th gen rapid test kit that showed negative. I asked him is that my conclusive result and he said yes. Is he correct? The clinic I consulted has good review on google. Any idea Mr.josh?
Hi Mohamed, you are low risk. The symptoms that you have been experiencing can be caused by your current infection/treatment, side effect from PEP or even stress. It is least likely that these symptoms are caused by HIV. Feeling uneasy is common before testing and after an exposure. Are you able to speak with anyone about how stressed you are? A 3rd generation test will only be suitable 90 days after your last dose of PEP. A 4th generation test can be used 42 days after.
Thank you josh for replying. I visit the doctor yesterday after I notice that I have unration pain with cold without fever and the skin of penis is dry and itchy and with secretions that stick without color after urination, but when rubbed, they turn white like the color of semen . he said probably is gonorrhea . He check from my penis and he give me ceftrriaxon 500mg as a injection and 2pills one time from zithromax . I tell him about all symptoms he said probably it’s all symptoms that I have when iwas use pep it’s could be from side effect . I’m 8 days now after finish pep yesterday iwas feel so cold and chills but when I test temperature from mouth is not more than 37,1C degree +A red sore on my inner lip. Is this a bad signe Knowing that I adhered to the medication for a full 28 days without missing a time or a dose, and even the exposure that happened to me was the condom slipping, as during the withdrawal process, I found the condom hanging from the vagina while she was menstruating, and I do not know if I inserted the penis without a condom and did not feel. I am really in a difficult psychological state waiting like death. Death is more merciful than this torment . My question, please, is this coldness and chills could be of a psychological cause? + I buy a rapid HIV test 3 generation when I can use it some they said it’s impossible to you have symptoms and you test negative is that true ? And thank you very much for your time. I am really very grateful to you ?
Hi Mohamed, being stressed around potential HIV exposures is not uncommon. Have you been able to speak with anyone about this? It is a good sign that you have tested negative but you will need a confirmatory test. You do not need to wait 6 months. A 4th generation antigen/antibody test will be conclusive from 6 weeks after the last dose of PEP. Rectal bleeding is not a side effect of this treatment, have you spoken to a doctor about this symptom?
Hello, how are you . I finished my 28 pep course last Saturday 11/02/2023. I was in a dangerous relationship with a girl who had slipped my condom and she was menstruating. Pep started within 10 to 11 hours. The mix is tdf-3tc-dtg. While taking this remedy, after 3 to 4 days, I began to suffer from pain in the rectum with bloody stools, and it continued for 21 days after that. After that, bouts of chills, the last of which was maybe 3 times during the treatment, the last of which was 5 days before the end of the course of treatment. I also lost a little weight, but now after the end of the treatment, I started to regain it. And petechiae on the arm and a rash close to black as spots. In addition to other side purposes, such as insomnia and sweating from time to time, I was constantly measuring fever. It did not exceed, most of the time, when measured from the mouth, 37.5 degrees Celsius. Yesterday, it was a month after exposure. I underwent a rapid test, thank God, it is negative, and I have to repeat it after 6 months. I want to ask, please, because I am in a bad psychological state. Is rectal bleeding a side effect of this mixture? Please answer, can medications cause this because I really read terrifying things on the internet about primary infectionand alast question did the negative rapid test after 30days from exposure is a good signe that all this symptoms it’s was from the side effects of medc I know I still need to wait . Thank you
Hi A, why are you continuing with PEP? After 28 days there is no further benefit to taking PEP. It will have either worked or not. At i-base we are not doctors and I cannot advise on what medications to take and when. Are you able to speak with your doctor about this?
Today is my 28th day of PEP. There is no more itchy red rashes (skin sometime itchy) but new non-itchy red rashes still appearing on my body and some are gone. I’m keep taking my PEP course whatever the matter I’m having. My body feels like hot and kinda having feeling like illness but when I measure temperature, it always shows 36.4-36.8 Celsius. And sometime having sore throat. Can I take 500mg Paracetamol (2 pills) , 250mg Amoxicillin (1pill) and 100mg Cevit (2pills) for 3 times daily? Having fun one time got a lot of anxiety and problem. OMG. Thank you Mr.josh