Recently had a drunken one time incident with a trans sex worker in UK. She said she is on prep and clean. Had protected insertive anal (anlthough I was drunk so can’t guarantee condom remained in place the whole time)  and unprotected oral both ways.

In my regret the day after a took 200mg doxycycline and then on second day 400g Cefixime and 2g Azithromycin. I am continuing to take 200mg doxy per day for 14 days.

Am I likely to have mitigated risk of most bacterial infection?

Also what’s the risk of HIV or HeP B for example? I’m going mad and will not drink again.

This was a pretty low risk event. Even if you con't recall if the condom remained in place, apparently you used one -- and once in place is unlikely to come off during anal sex. So most likely it was protected. And oral sex is inherently low risk. It also sounds like your partner is aware of the risks and cares for her health, as reflected in her being on HIV PrEP and "clean". (Most people are truthful about such things.) Even if not, I would have advised against the post-exposure antibiotics. And even then, you are being over treated. Maximum protection against the bacterial STDs (gonorrhea, chlamydia, syphilis) was achieved with the cefixime and the first 200 mg dose of doxycycline, which is nearly 100% effective in preventing syphilis and chlamydia (and cefixime is effective against gonorrhea). Continuing doxycycline does not improve protection and only increases your risks of future antibiotic-resistant infection. Please stop taking it.

Those comments answer your question about bacterial STIs. For HIV, it is extremely unlikely your partner has it, based on her taking PrEP. And if she did, your risk remains low, especially with a condom and even if the exposure was partly unprotected. Hepatitis B virus (HBV)? How old are you? Assuming no more than 30 or so, almost certainly you are protected by childhood immunization, which I believe was routine in the UK by the time you were in early childhood. Even if not vaccinated, almost certainly your partner was an cannot possibly be a carrier. Because of widespread immunization, sexually transmitted HBV is now rare in industrialized countries. If you doubt and cannot confirm your vaccination status, a simple blood test can determine if you are susceptible.

Based on these facts, I would consider HIV testing optional. But if you would like the reassurance of a negative blood test, you could do that with an AgAb (4th generation) blood test 6 weeks after exposure, or perhaps a PCR RNA test at 11 days. Given the antibiotics, there is no now point in testing for gonorrhea, chlamydia or syphilis. You might consider contacting your nearest NHS GUM clinic for personalized advice on all this. But in the meantime, you really should not be worried. It is very likely you don't have any infection at all.

I hope these comments are helpful. Let me know if anything isn't clear.

HHH, MD

I’m presuming it’s far easier to cure an infection in the incubating period. On that basis would you be quite sure the doxycycline will have dealt with syphillis and the 2g azith/ 400mg cefixime combo dealt with gonorrhoea (either throat or urethral?).

Additionally I’m mid 30s so I don’t believe I’ve been vaccinated against Hep B. However it appears a low risk from your response?

I appreciate the rapid response by the way.

Jon

You "reduce[d] the risks as far as possible" with cefixime and the first dose of doxycycline. The azithromycin made no difference and neither would the additional 13 doses of doxycycline. Don't take them. Correct that the dose need to prevent infection before it takes hold is far lower than necessary to cure established infection, which is why one dose of doxy protects against chlamydia and syphilis.

That concludes this thread. I hope the discussion has been helpful. Best wishes and keep safe.---
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