Can you get HIV or STIs from oral sex?

Sucking dick is one of the great joys of gay life, and the good news comes first: it’s about the lowest-risk thing you can do for HIV. The less famous news is that your throat is a very popular hangout for gonorrhea. Here’s how it all actually works.

The HIV risk, by what you’re doing

The CDC estimates HIV risk per act when one partner has HIV and isn’t on treatment. Oral sex is so low that it’s listed as “low” with no number.

And those numbers drop to zero in practice when the guy with HIV is on treatment with an undetectable viral load, or when you’re on PrEP. The American Sexual Health Association says there have been few, if any, known cases of HIV passed through oral sex.

The STIs that do spread through your mouth

San Francisco City Clinic keeps a plain list of what spreads through each kind of play:

Your throat and gonorrhea

Researchers at the Melbourne Sexual Health Centre in Australia have spent years studying how gay and bi men get throat gonorrhea, and kissing kept coming up.

In a survey of about 3,700 gay and bi men tested at the clinic in 2016 and 2017, about 6% had gonorrhea in their throat. Men with more kissing partners were more likely to have it, while men who had sex without kissing were not. A separate study of 60 male couples found that when one partner had gonorrhea in his ass, the other had it in his throat 34% of the time, far more than chance. The researchers think it passes through kissing, sucking, rimming and using spit as lube.

That’s not a reason to stop kissing anyone. It’s a reason to test your throat.

The CDC says most throat gonorrhea causes no symptoms, it’s harder to cure than gonorrhea in your dick or ass, and it may be one way the bacteria learn to resist antibiotics. Usually there’s nothing to notice at all, which is exactly why a swab matters.

How to stay on top of it

• Ask for a throat swab. Many clinics only test pee unless you ask. The CDC recommends gay and bi men test for gonorrhea at least once a year, and every 3 to 6 months at every site you use if you have more partners. Say “I’d like a throat and rectal swab, not just urine.” See How often should you get tested?
• Consider doxyPEP. A dose of doxycycline after sex covers oral sex too, and cuts syphilis and chlamydia a lot and gonorrhea by about half. See What is doxyPEP?
• Get vaccinated. Hepatitis A, hepatitis B, HPV and mpox all have vaccines. See Which vaccines do gay and bi men need?
• Condoms work for blowjobs too, if you want them. Most guys don’t use them for oral, and that’s a choice you get to make.
• If something feels off, like a sore throat that won’t quit, a sore on your lip or a burn when you pee, get checked rather than waiting it out.

Frequently asked questions

Can you get HIV from giving a blowjob?
The risk is very low. The CDC rates it as “low” without a number, and it’s effectively zero if your partner is undetectable or you’re on PrEP.

Can you get HIV from swallowing cum?
Cum can carry HIV, so swallowing adds a little risk compared with not, but oral sex is still very low risk overall. PrEP or a partner who’s undetectable takes it off the table.

What STIs can you get from oral sex?
Gonorrhea, chlamydia, syphilis, herpes, HPV and mpox. Rimming can also pass hepatitis A, shigella and other gut infections.

What are the symptoms of throat gonorrhea?
Usually none. Some people get a sore throat. That’s why a throat swab is the only way to know.

Do I need a throat swab if I only give head?
Yes. Giving head is exactly how gonorrhea and chlamydia get into your throat, and a urine test won’t find them there.

Sources: CDC: HIV risk behaviors, SF City Clinic: How STIs transmit, ASHA: Oral sex and STIs, aidsmap on the Melbourne throat gonorrhea studies (Sexually Transmitted Infections, 2019), CDC STI Treatment Guidelines: gonorrhea.