Question
Does PEP delay seroconversion?
24 December 2021. Related: All topics, PEP/PEPSE.
Hi, I had an exposure in early October.
I took PEP (TDF + FTC + DTG) after 5 hours of the exposure. I did not accompany the doses with meals, I took them alone with water or some drink. Can this interfere or reduce its effectiveness?
Does PEP delay seroconversion in case of failure? At 5 weeks after finishing PEP swollen lymph glands in both armpit.
Answer
Hi, how are you doing?
PEP does have the potential to delay seroconversion.
As PEP works similar to medication used to manage HIV, PEP if unsuccessful can delay seroconversion.
This is why testing a minimum of 4 weeks after PEP is required. Seroconversion can occur 1-3 weeks after the course ends. Only 80% of those who do seroconvert in failed PEP will experience classical symptoms e.g., fatigue, fever, headache etc.
Five weeks after finishing PEP would be later than expected if this was really HIV. Swollen lymph nodes can arise from a number of infections, not only HIV. Is this symptom being managed by a doctor?
The combination you have taken can be consumed with or without food. This would not have impacted how well it worked as PEP.
If you have another question do ask,
Josh.
Hi John, after 42 days your test is conclusive. You do not need any further testing. You are HIV negative. Please follow this link for further information: https://i-base.info/qa/factsheets/hiv-transmission-and-testing
Hello Josh. I had an ag/ab test at 47 days after last dose of pep or 74 days after risky sex. Test turned out negative. I keep reading stuff online saying this may not be conclusive. Going crazy with this. Appreciate your help thank you
Hi KK, a 4th generation test from 28 days is 95% accurate. This means your sore throat is very unlikely to be caused by HIV. The result becomes conclusive from 42 days after PEP. A sore throat is a very common symptom of a number of infections. As this your main symptom it is more likely that this is an isolated sore throat than being caused by HIV.
Hi Josh, thanks for your response.
Let me rephrase my question though. Since day 28th after completing PEP, I experienced some symptoms like sore throat and kind of rash. On day 35th after completing PEP, I went for 4th generation HIV test which came negative. On day 36th after PEP I still have sore throat.
So, my question is does my 35th day test conclude that the sore throat is not HIV related. Or it could still be HIV related?
Hi KK, after 35 days it would not be expected for you to experience seroconversion. In most cases, this is experienced 1-3 weeks after exposure (after the end of PEP). 20% of people will not experience seroconversion at all.
Hi Josh,
Is seroconversion possible after 35 days of completing last dose of PEP?
Hi Josh,
I finished my PEP medication on 29th October after an unprotected vaginal sex. On 8th November, I had the following tests:
1. HIV 4th generation Antigen + Antibodies lab test.
2. HIV DNA PCR Pro-viral (NAT) test.
3. Complete STD profile.
All of these tests came negative.
Then on 27th November, I had another 4th generation test for HIV. It came negative too.
However, on 28th November (night) I started feeling irritation on my chest and abdomen area and on 30th November (morning), after taking shower, I noticed many red spots on my chest and upper abdomen area (kind of rash which don’t ich or pain). I also had sore throat from 25th to 29th November.
By 1st December, the rashes (red spots) are almost gone. However, I’m feeling kind of sore throat again.
Am I seroconverting in the beginning of 5th week after completing PEP?
Hi Jessy, this does not suggest PEP has failed. The ear infection that you have had can be attributed for what you have experienced since stopping PEP.
You can test now to help with anxiety. The result will be more than 95% accurate. Then the following test at 6 weeks will be concussive.
Hi. I had a case of condom burst twice while being with a girl of unknown status. It was pretty much my first time I would say. I started PEP (TLD) at the 33 hour mark of possible exposure. I had no side effects of PEP save fatigue and tiredness. However, few days after completing PEP, I had sore throat and mild headache. A week and two days after PEP, I had a swollen gland behind my neck, to be specific, behind my ear. I went to the hospital and was diagnosed of an ear infection because there was heavy growth of streptococcus in that ear. Besides, blood analysis return lymph % to be 56 Percent. I was given antibiotics and an ear drop. The swollen gland has reduced but not completely gone at 5weeks post PEP. Sore throat have just only significantly improve as the pain is quite mild and sometimes not there. I do not have difficulty swallowing. But I still have mild headache and sometimes tiredness. I am waiting for the 6th week to go for another test. What do u think? Do u think PEP failed?
Hi Percy, while you were taking PEP you would have been protected from the further exposures you had. While taking PEP, it acts as PrEP for the duration of the course. You can’t test immediately after finishing PEP. You will need to test a minimum of 6 weeks after your last dose of PEP – PEP can delay seroconversion and cause tests to be inaccurate.
Are you taking Truvada? It is possible that these symptoms are caused by PrEP though it is unlikely. Do you have a fever? Seroconversion would not be expected this early after finishing PEP. Seroconversion usually occurs 2-3 weeks after the last dose. As symptoms can be quite general, it is most likely they are being caused by a different infection. If they persist or start impacting living, speak with your doctor/pharmacist.