STDs Forum
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Hi Doc,

I have a few questions that I can't find answers to elsewhere.  

1) The common wisdom seems to be that Listerine (or some other antiseptic mouthwash) before and after unprotected oral sex reduces the risk of STD transmission.  I've also heard of using same on the genitals following genital contact.  Is there any evidence for this?  It seems plausible, though more for bacterial STDs than viral STDs. Would you recommend it?

2) You've said repeatedly that the risk of picking up STDs from a single act of unprotected oral sex is low, but not zero.  I've read many reports (seemingly reliable) from people who have picked it up this way.  Any idea of whether the risk of picking some STD (Chlamydia, Syphilis, Gonorrhea, Herpes) from one such act is more like 1 in 1,000 or 1 in 100,000? I realize it depends on many factors, and there probably are no perfect studies, I'm just looking for general guidance based on your personal experience.

3) Suppose a person has some unexpired Cipro, which apparently works against many types of bacterial infections. After engaging in unprotected oral sex with several different high-risk partners (say, 10) in short period of time while on vacation, would it make sense to use the Cipro as a preventative measure?  My guess would be "no, not unless you actually show symptoms". Everyone says you shouldn't abuse anti-biotics. On the other hand, STDs are no fun at all, I've heard.      

4) I read on this board that most people already have non-genital HSV-1 (often from childhood), usually non-recurring with little or no asymptomatic shedding, making them virtually immune to contracting genital HSV-1.  This seems to suggest that it would actually be a "good" thing to have the (mild) non-genital HSV-1, becaues it would prevent the much worse genital HSV-1 scenario. Would it be feasible to acquire it on purpose? Is there some danger I'm overlooking (I'm obviously no expert here).

5) If use of antibiotics can lead to antibiotic-resistent strains of the disease, can condom use lead to condom-resistent strains?  (Just kidding!)
1 Responses
239123 tn?1267647614
Straight to your questions.

1) Topical antiseptics, including listerine, have not been studied for their effectiveness in STD prevention. The best guess, based on distant past experience with other antiseptics (from thw WW II era) suggests little effect.  Washing after sex can't hurt, but I doubt using listerine, alcohol, etc does not any difference beyond the minor benefit of soap and water.

2) There are no data on the per-exposure risks from oral sex for any STD other than HIV.  In general, the risk is believed to be a lot higher than for HIV--except chlamydia, which infrequently infects the mouth or throat and for which transmission from mouth to genitals has never been documented.  

3) Periodic antibiotic therapy might make sense, but not with cipro.  Cipro is useless against gonorrhea in most of the world and in the US resistance is spreading rapidly (although it remains active in much of hte country, except in gay men).  Cipro is weakly active against chlamydia and entirely ineffective against syphilis.

4) There has been previous discussion on this forum about the potential benefits of HSV-1 to protect against HSV-2.  But HSV-1 has its own risks.  The chance of central nervous system infection is low, but when it occurs, it is absolutely devastating--like having a bad stroke.  Put another way, rare HSV-1 infections are fatal; HSV-2 infections never are.  I don't recommend that anybody intentionally seek HSV-1 infection to protect against genital HSV-2.

5) Cute.  No.

Best wishes--  HHH, MD
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