Recently a patient asked about pre-exposure prophylaxis. He described himself as a "hobbyist," and explained that he often gives and receives unprotected oral sex with high risk partners. He asked if there were any medications that he could take to minimize the risk of infection, should he be exposed.
Well, there are no currently approved FDA protocols for pre-exposure prophylaxis. However, we do have post-exposure protocols which, with slight modification, should protect almost anyone against the most commonly transmitted STD's found in the high risk community.
The most common STD transmitted through oral sex is herpes (both type1 and type 2). While there are currently no FDA approved pre-exposure treatments, 1 gram of Valtrex, taken the day of exposure (preferably before the exposure) seems to offer very good protection.
Other common STD's transmitted orally include Chlamydia and Gonorrhea. With 4 tablets of Azithromycin, both of these conditions can be cured. However, to prevent, the old axiom "an once of prevention is worth a pound of cure" holds true, and as few as 2 tablets should do the trick (if taken within hours of exposure).
Syphilis is most easily addressed with either a shot (Rocephin) or single pill (Suprax 400 mg). Most other possible bacterial or protozoal infections are well covered with 2-4 tablets of Flagyl (500 mg) as a single dose (the number depending upon whether it is pre- or post- exposure).
Finally, all patients should be vaccinated against hepatitis B.