From my last conversation with Dr. Hook. I've been eased a lot. Also, I've discussed with local doctors here. They agree with Dr. Hook's opinion. I've also read different guidelines from different organizations. I found the longest window period after PEP is 4 months after the encounter. 

     What confused me a little is that I found in other threads that Dr. Handsfield mentioned  after completion of PEP, 'You need to wait until at least 3 months after the exposure for conclusive testing, and some experts recommend 6 months.' I respect your expertise. Could you help clarify this? Under what circumstance is a six-month testing needed?

No data exist on time for delayed testing after PEP -- none. All recommendations are based on common sense beliefs by providers based on their interpretation of the scant available data. Some might say 3 months, others 4 months, some 6 months, and once in a while even a year. It is possible that the tiime to reliable testing isn't altered at all by PEP, and certainly any test more than 6 weeks after esposure is highly reliable, if not truly conclusive. It is difficult to criticize any experts who might recommend these different intervals.

Something many people misunderstnad is the relationship between testing and symptoms. The symptoms of ARS are caused by the immune response to HIV, not the virus itself. Therefore, when symptoms are due to HIV, the blood tests are always positive. No exceptions. So the tests you have had prove for sure that any symptoms you have, or might ever have in the future, are not from HIV. Probably they also are reliable in proving you didn't catch HIV (without symptoms). But you should follow your own doctor's or clinic's advice about the final date of testing.

HHH, MD

Honestly I've been connecting any tiny symptom with possible HIV infection because the possible delayed seroconversion after PEP.  And I somehow regret having taken PEP. And this regret makes me anxious. My doctor says I'm fine. But I'm still worried about the possible delay seroconversion, symptoms, and testings. Doctor, could you please give me some advice on how to get rid of it?  Thans a lot.

From your words, I know that there is no exact data on window period and no 100% guarantee. How can I correctly understand the possibility of HIV infection, symptoms and testing? In the following day, under what circumstance do I need to get tested?  Could you please evaluate my risk in terms of HIV. I'm really freaked out  and regretful on my decision to take PEP. Sorry again!

I'm not sure if you're also asking when to be teste in event of future exposures that may be risky for HIV. In case you are, I would say there are two situations:  First, get tested following any truly high risk exposure, such as unprotected vaginal sex or anal sex with someone who is known to have HIV or believed to be at high risk. But it's not necessary to be tested if a condom is used, or if the only such exposure is oral sex or hand-genital contact. Second, if you have ongoing potentially risky events -- but no failed condoms or other things that raise the risk -- all sexually active people should be tested for HIV from time to time, like once a year. In most cases that testing should also include gonorrhea, chlamydia, and syphilis. All HIV testing usually should be done with an AgAb (duo, 4th generation) blood test about 6 weeks after the most recent risky event, although it's OK to also test at 3-4 weeks, when the results are over 90% reliable and therefore should be reassuring.

As for "evaluate my risk in terms of HIV", Dr. Hook addressed that in detail in your previous thread last month. Re-read his advice. You were not at risk at all and should not be putting yourself through all this agony, including PEP. But now that you've done it, you probably should continue -- again, check back with the doctor who prescribed it.

As to your anxious and mostly irrational fears, that's a psychological issue and this site has no advice about such issues. But if your fears continue, you should consider professional counseoling. Start with your doctor. I suggest this from compassion, not criticism.