Can You Get an STI From Oral Sex? Risks and Testing Explained

Many people use condoms for vaginal or anal sex but not for oral sex, and assume that keeps them safe. It reduces some risks, but the mouth and throat can still pick up or pass on several sexually transmitted infections (STIs). Here's which infections can spread through oral sex, what they look like, and how an STI test after oral sex works.

Can You Get an STI From Oral Sex?

Yes. Anyone, of any gender, can get an STI from oral sex without a condom or dental dam if their partner has an infection. It works both ways. Giving oral sex can pass an infection from your partner's genitals or anus to your throat, and receiving it can pass an infection from their mouth or throat to your genitals. You can also have an STI in your throat and your genitals at the same time.

Some things raise the risk, such as sores or cuts in the mouth, bleeding or inflamed gums, or sores on a partner's genitals. And as with other sex, many infections cause no symptoms early on, so a partner may not know they have one.

Which STIs Can Be Passed On Through Oral Sex?

Oral-anal contact (rimming) can also spread hepatitis A, and gut infections such as Shigella and Giardia. Throat chlamydia or gonorrhoea may also slightly raise the risk of HIV.

Symptoms of an STI From Oral Sex

Most throat infections cause no symptoms at all. When they do, different infections can look alike:

• A sore throat that won't go away, even after the usual remedies
• Sores, blisters, ulcers or red patches in the mouth, on the lips or tongue, or in the throat
• Pain when swallowing
• Swollen, tender glands in the neck or under the jaw
• Warts in the mouth or throat (rarely, from HPV)

If the infection was passed to your genitals by someone giving you oral sex, the symptoms are the same as for any genital STI: discharge, burning when you pee, sores or blisters. Our guide to chlamydia vs gonorrhoea covers the most common ones. And because so many infections are silent, see STIs without symptoms too.

What Increases the Risk of an STI From Oral Sex?

• Having oral sex without a condom or dental dam
• Having several partners, or a new partner whose status you don't know
• Giving oral sex when you have mouth ulcers, cuts, bleeding gums or gum disease
• Receiving oral sex when you have sores or cuts on your genitals, or from someone with a cold sore
• Contact with semen or other fluids in the mouth

How to Reduce the Risk of an STI From Oral Sex

• Use a barrier. A condom for oral sex on a penis; a dental dam (or a condom cut open into a square) for oral sex on a vagina or anus.
• Skip oral sex when either of you has a sore. That includes cold sores, mouth ulcers, bleeding gums and any sore or rash on the genitals.
• Get vaccinated. The HPV vaccine and the hepatitis B vaccine prevent two infections that oral sex can spread.
• Test regularly, including a throat swab if you have oral sex with new or casual partners.
• Have fewer partners, or talk about testing before you stop using barriers with someone new.

STI Testing After Oral Sex

Testing tells you where you stand and gets you treated early if you need it, which also protects your partners. After oral sex, the tests depend on which infections you're checking for:

• Throat swab for gonorrhoea and chlamydia. A soft swab is wiped over the back of your throat and tonsils and sent for a PCR (NAAT) test. This is the step people most often miss: a urine test cannot find a throat infection.
• Swab of a sore for herpes, if you have a blister or ulcer. It works best on a fresh sore.
• Blood tests for syphilis and HIV, and for hepatitis B if you're not vaccinated.
• Urine or genital swabs if you received oral sex, to check your genitals.

Timing matters, because a test taken too early can miss an infection. For gonorrhoea and chlamydia, test about 2 weeks after the oral sex. A 4th generation HIV blood test can usually detect HIV from 18 to 45 days. For syphilis, have a final test at 12 weeks. If you have symptoms, test straight away; the doctor will tell you if you need to repeat anything later. Our STI test window calculator works out the dates for you.

Where to Get Tested for STIs From Oral Sex in Bangkok

Public and private hospitals and clinics in Bangkok can test you after oral sex, as long as you ask for a throat swab. For more privacy and convenience, Ovio's at-home STI testing comes to your home, condo, hotel or office. Pick the date, time, place and tests. A doctor takes the throat swab and any blood tests you need, results come back promptly and confidentially, and we can advise on what to test for based on what happened. We look after both Thai and international clients.

If it's gonorrhoea you're most worried about, the gonorrhoea test page explains throat swabs in more detail. For sores, see the herpes test.

Frequently Asked Questions

What is the most common STI from oral sex?

Gonorrhoea and herpes are among the most common. HPV is also very common, but it rarely causes symptoms.

Can you get HIV from oral sex?

It's very unlikely. The CDC says there's little to no risk of HIV from oral sex. The risk is higher if there are cuts, sores or bleeding gums, but it stays far lower than for vaginal or anal sex.

Can you get chlamydia in your throat?

Yes, though it's less common than gonorrhoea in the throat and usually causes no symptoms. A throat swab will find it.

Is giving or receiving oral sex riskier?

It depends on the infection. Gonorrhoea, chlamydia and syphilis pass easily from genitals to throat when giving oral sex. Herpes from a cold sore passes easily to the genitals when receiving it. Both carry some risk.

Will a urine test show an STI in my throat?

No. A urine test only checks the urethra and genitals. To check your throat you need a throat swab.

How soon after oral sex should I get tested?

About 2 weeks for gonorrhoea and chlamydia, 18 to 45 days for HIV with a 4th generation test, and 12 weeks for a final syphilis test. Test right away if you have symptoms.