I had unprotected oral sex. Should I get tested?

Yes, if you have had unprotected oral sex with a new or casual partner, or with a partner who has an STI or symptoms of one. Many STIs that spread through oral sex cause no symptoms, so testing is the only way to know for sure.

Chlamydia, Gonorrhoea and Syphilis can be cured with antibiotics, and antiviral medicine can help with Herpes outbreaks, but only if you know you have an infection. Testing also protects your partners, because you can pass on an infection without knowing you have it.

Oral sex is when someone uses their mouth, lips or tongue to stimulate a partner’s penis, vagina or anus. Oral sex on the anus is often called rimming.

Oral sex is unprotected when you don’t use a barrier, such as a condom on the penis or a dental dam over the vagina or anus. A dental dam is a thin, soft square of latex or plastic. If you don’t have one, you can cut open a condom to make a square.

When you give oral sex, an infection on your partner’s penis, vagina or anus can pass to your mouth or throat. You can catch:

• Chlamydia and Gonorrhoea. Both can infect the throat. Throat infections usually cause no symptoms, although some people get a sore throat.
• Syphilis, through contact with a Syphilis sore on your partner’s genitals or anus. The sore is usually painless, so your partner may not know it is there.
• Herpes, if your partner has genital Herpes. The virus can pass to your mouth or lips.
• HPV, which can infect the mouth and throat. HPV usually causes no symptoms and clears up on its own, but high-risk types are linked to some head and neck cancers. In the UK, HPV causes around half of all oropharyngeal cancers, which include cancers of the tonsils and the back of the tongue.
• Hepatitis A and Shigella, a gut infection, which spread through poo during rimming.

Hepatitis B can also be passed on through oral sex. Your risk of catching HIV from giving oral sex is very low. Read more in “Can you get HIV from oral sex?”

When you receive oral sex, an infection in your partner’s mouth or throat can pass to your genitals or anus. You can catch:

• Herpes, if your partner has a cold sore. HSV-1, the virus that usually causes cold sores, can cause genital Herpes if it is passed on through oral sex. Cold sores are contagious from the first tingle until they have fully healed, so avoid oral sex until then.
• Syphilis, if your partner has a Syphilis sore on their lips or inside their mouth.
• Gonorrhoea. Studies disagree on how often Gonorrhoea passes from the throat to the penis. A US study of men who have sex with men estimated that about a third of Gonorrhoea infections in the urethra with symptoms came from oral sex, but a later Australian study found no clear link.
• Non-specific urethritis (NSU), which is inflammation of the urethra, the tube that carries pee out of the body. Some cases are caused by germs from the throat. Adenovirus can be passed on through oral sex, and the bacteria Haemophilus influenzae may be too.

There is less evidence that Chlamydia passes from the throat to the genitals, but it can’t be ruled out.

There isn’t an exact figure. Your risk depends on the infection, whether your partner has it, and what kind of oral sex you have.

For HIV, the risk from oral sex is very low: the CDC says there is little to no risk of getting or passing on HIV this way. For other infections, oral sex is a real route. In one US study of people with Syphilis, about 1 in 7 said oral sex was their only sexual contact.

According to the CDC, these things may make it easier to catch an STI from oral sex, although no studies have shown whether they do:

• poor oral health, such as tooth decay, gum disease or bleeding gums
• sores in the mouth or on the genitals
• contact with pre-cum or cum

Many STIs caught through oral sex cause no symptoms at all. Chlamydia and Gonorrhoea in the throat usually have no symptoms, although some people get a sore throat.

If you gave oral sex, look out for:

• a sore throat
• blisters, sores or ulcers on or around your lips or inside your mouth
• tingling, itching or burning around your mouth, which can come before a cold sore

If you received oral sex, look out for:

• pain or burning when you pee
• unusual discharge from the penis, vagina or anus
• blisters, sores, lumps or itching around your genitals or anus

Some infections, such as Syphilis and HIV, can also cause a rash, flu-like symptoms or swollen glands weeks or months later. If you notice any symptoms, get tested, even if you have tested recently. Read more in “What is an oral sexually transmitted infection?”

You can test for Chlamydia and Gonorrhoea from 14 days after oral sex, but some other infections take longer to show up on a test. Testing too early may miss an infection, because it needs time to reach a level a test can pick up. This is called the window period, and it is different for each infection.

• Chlamydia and Gonorrhoea: test from 14 days after oral sex. A test taken earlier can’t rule them out.
• Syphilis: an early test can miss it, so UK guidance recommends a repeat test 3 months after a risky contact.
• HIV: UK guidance gives a window period of 45 days for a fourth-generation laboratory test. The risk of HIV from oral sex is very low.
• Herpes: a blood test can miss an infection caught in the last 12 weeks. If you have a sore, a swab taken from the sore is the most reliable test.

If you test earlier than this, you may need a repeat test for Syphilis, HIV or Herpes later. If you have symptoms, don’t wait. Book a test straight away and tell the clinician when you had oral sex.

The right test depends on the kind of oral sex you had and whether you have symptoms. A urine test won’t pick up an infection in your throat, so if you gave oral sex, you need a throat swab.

• Oral Screen home test: for anyone who has given or received oral sex. It tests a throat swab and a urine sample for Chlamydia and Gonorrhoea, and a blood sample for Syphilis, Herpes 1 and Herpes 2. You can test from 14 days (28 days for Herpes), with results within 2 days of your samples reaching our laboratory.
• Chlamydia and Gonorrhoea (Throat Swab): if you gave oral sex and want to check your throat only. You can test from 14 days at one of our clinics or with a home test kit, with results in 2 days.
• Herpes Simplex Type 1 and 2 (Swab): if you have a sore or blister on or around your mouth or genitals, this test checks a swab from it for Herpes.
• Blemish Screen: if you have a sore, blister or lump on or around your genitals, this tests a swab for Herpes 1, Herpes 2, HPV and Syphilis.
• Confidence Screen: a wider check that adds throat and anal swabs for Chlamydia and Gonorrhoea to our Full Screen, which includes HIV, Syphilis and Hepatitis B. You can test from 28 days.

Not sure which test you need? Our Patient Care Team is available 24/7 on 020 7099 0955.

You can lower your risk of catching an STI from oral sex by:

• using a condom for oral sex on a penis
• using a dental dam, or a condom cut open into a square, for oral sex on a vagina or anus
• not having oral sex when you or your partner has a cold sore, or any sores, blisters or warts around the mouth, genitals or anus
• washing your hands and changing condoms between anal sex and oral sex
• getting vaccinated against HPV, Hepatitis A and Hepatitis B if you are eligible
• testing regularly if you have new or casual partners

In the UK, vaccines against Hepatitis A and Hepatitis B are recommended for gay, bisexual and other men who have sex with men, and the HPV vaccine is offered to men who have sex with men aged 45 and under. The Hepatitis B vaccine is also recommended for people who change sexual partners often and for sex workers.

Can you get HIV from oral sex?

The risk is very low. The CDC says there is little to no risk of getting or passing on HIV through oral sex. The risk may be higher if cum gets into the mouth and there are mouth ulcers, bleeding gums or genital sores, or if either partner has another STI.

Can you catch an STI from oral sex if nobody comes?

Yes. Herpes, HPV and Syphilis spread through skin contact, so you can catch them whether or not anyone ejaculates. Read more in “Can you pass on or contract an STI without ejaculation?”

Do you need a throat swab after giving oral sex?

Yes, if you want to check for Chlamydia and Gonorrhoea in your throat. A urine test only checks your genitals, so it won’t find an infection in your throat.

How often should you get tested if you have oral sex?

UK guidance says sexually active people should test once a year and after a new partner. If you have several new or casual partners, test every 3 months. Gay and bisexual men who have sex without condoms with new or casual partners are advised to test for HIV and STIs every 3 months.

Oral sex can pass on STIs whether you give it or receive it, and infections in the throat often cause no symptoms. If you have had unprotected oral sex with a new or casual partner, getting tested is the only way to know for sure.

Order an Oral Screen home test, or book a test at a clinic near you. Our Patient Care Team is available 24/7 on 020 7099 0955 to help you choose the right test.

Not in the UK? Choose your country from the selector at the top of the page for local tests and prices.

This article originally appeared on 10 March 2023 and was last updated on 30 September 2026.

This article is general information and not a substitute for personal medical advice.

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