Your self assessment of risk is correct:  a single oral sex exposure is inherently low risk. However, more detail would help judge this in more detail:  Was your partner male or female? Do you mean a partner took your penis in their mouth, or were your mouth and throat exposed?

Doxypep is recommended only for unprotected anal sex between men, not oral sex. The risks from oral sex are generally too low to require PEP. That said, you are correct that in the standard dose of 200 mg within 72 hours of exposure, doxypep is nearly 100% effective in preventing syphilis and chlamydia and about 50% against gonorrhea.

I might have further comments after you clarify the exposure. I hope this information is helpful in the meantime.

HHH, MD

Absence of discharge from the penis and painful urination (within 3-5 days) is strong evidence against urethral gonorrhea. However, oral gonorrhea usually causes no symptoms. The only way to be completely certain you did not acquire is to be tested for it  -- urine and a throat swab. (However, the chance you were infected probably is very low. If somehow I were in your situation, I would not have taken doxypep, would not be tested for anything, and would continue unprotected sex with my wife without worry.

The chance of genital HSV1 from oral-to-penile contact probably averages under one chance in several thousand, but it depends on several factors unknown to me and perhaps to you as well: Whether you ever had HSV1 previously, like half the US population (in which case you're immune); chance your partner has oral HSV1; if so, whether he was having an outbreak or shedding the virus at the time. In addition, who cares? Genital HSV1 usually recurs infrequently if at all and is almost never transmitted to sex partners, and ongoing treatment therefore is unnecessary. So most infected people have no problem with it.