Rimming: the health risks and how to reduce them

Rimming means licking around a partner's anus. Because tiny traces of poo can reach the mouth, it can pass on infections such as shigella and hepatitis A, and some sexually transmitted infections (STIs) can pass on too. This page sets out what UK health services and research say about the risks of rimming and how to lower them, whoever you are and whoever you're with.

What is rimming?

Rimming is licking around the anus during sex. Brook, a UK sexual health charity, lists it as one type of anal sex and gives its other names, a rim job and analingus, which have the same meaning. UK health services also call it oral-anal or anal-oral sex, and you'll see it spelt rimjob and anilingus too.

As with any kind of sex, some people enjoy it and some don't, and Brook says it's perfectly normal to try anal sex and decide you don't like it. Its advice starts with consent: anal sex should be discussed and agreed beforehand, even if someone has already agreed to another type of sex, and either of you can stop at any point.

Is rimming safe or dangerous?

Rimming carries a real risk of infection, though there are ways to lower it. The UK Health Security Agency (UKHSA) names anal-oral sex ("rimming") as one way shigella spreads, and the Terrence Higgins Trust (THT) names it for hepatitis A and B. Sheffield's NHS sexual health service says STIs can pass on through any type of sex, rimming included.

Infections carried in poo spread this way because so little is needed. UKHSA says shigella's infectious dose is very low, so swallowing just a tiny amount of contaminated material can be enough to cause illness. THT says the hepatitis A virus lives in poo and needs to get into the mouth to infect someone, which can happen during sex when tiny amounts get on fingers and into mouths.

Someone can feel fine and still pass an infection on. UKHSA says some people carry and pass on shigella without feeling ill themselves, and the NHS says many STIs have no symptoms.

Which infections can rimming pass on?

Going by UK sources, the infections that can pass on through rimming fall into two groups: infections carried in poo, such as shigella, hepatitis A, E. coli, salmonella and giardiasis, and infections spread through body fluids, skin contact or sores, such as hepatitis B, herpes, syphilis and genital warts.

Infections rimming can pass on, and the protection the sources name

	How it can pass on.	Protection named in the sources.
Shigella	Bacteria in poo; UKHSA names anal-oral sex ("rimming") as one way it spreads	A barrier, washing your hands after sex, and a shower if possible
Hepatitis A	A virus in poo; the Terrence Higgins Trust names rimming	A vaccine (the NHS names men who have sex with men among those at high risk who need it), a barrier and handwashing
Hepatitis B	Body fluids including blood, semen and vaginal fluids; the Terrence Higgins Trust names rimming	A vaccine for people at high risk, including anyone with multiple sexual partners and men who have sex with men
E. coli and salmonella	Bacteria; Brook lists both among infections passed on through oral to anal sex	Gently washing the area first with water and gentle soap
Giardiasis	A gut infection; the NHS says it can spread through sex, especially unprotected anal or oral sex	The NHS advises frequent handwashing if you have it
Herpes	Skin-to-skin contact with the infected area, including oral and anal sex	No sex while there are blisters, sores or the tingle of an outbreak; a barrier only protects the skin it covers
Syphilis	Contact with a syphilis sore, which can be around the anus or inside the mouth	A barrier, and testing at a sexual health clinic
Genital warts (HPV)	Skin-to-skin contact; the NHS says spread through oral sex is rare	The HPV vaccine, offered to men up to and including 45 who have sex with men, and some others

"A barrier" means a dental dam, or a condom cut into a square. The Terrence Higgins Trust says you may be able to get the hepatitis A and B vaccines free from a GP or sexual health clinic.

What does the research say about rimming and infection?

Of the studies on this page, the clearest link is with shigella. A study in San Francisco compared 76 adults who had shigellosis with 146 who didn't, in 1998 and 1999. In men, direct oral-anal contact was linked with about 7.5 times the odds of infection; in women, only travel abroad was linked.

The other things linked with infection in men were being a man who has sex with men, having HIV and travelling abroad. The authors concluded that among men who have sex with men, shigellosis is mainly a sexually transmitted infection, with direct oral-anal contact carrying the highest risk. It was one US city, with small numbers, more than 25 years ago.

A UK study looked at an outbreak of one strain of shigella (Shigella flexneri 3a) in England and Wales. Of the men Public Health England researchers interviewed after diagnoses between October 2012 and May 2013, 34 were sexually active men who have sex with men, and all 34 reported oral-anal contact. Everyone in that study had the infection, so it shows how common rimming was among them but can't measure how much it raised the risk.

Two studies at the Melbourne Sexual Health Centre in Australia found no statistically significant link between rimming and gonorrhoea. In a survey of 1,312 men who have sex with men in 2014 and 2015, being rimmed was not statistically linked with gonorrhoea in the rectum, though using a partner's saliva as lube was. In a study carried out in 2015, comparing 177 men who had throat gonorrhoea with 354 who didn't, rimming a partner was not statistically linked with throat infection either. That study's authors said more research is needed on how likely gonorrhoea is to pass on through specific sex acts. The results also say nothing about other STIs: herpes, syphilis and warts spread through skin contact and sores, as the table shows.

A 2022 review in the journal Clinical Infectious Diseases described "a robust body of literature" on the sexual transmission of three gut infections, Campylobacter, Giardia and Shigella, among men who have sex with men. It also noted an acknowledged lack of evidence on which prevention strategies work. Most of the studies on this page are in men who have sex with men, but UKHSA says anyone can get shigella. UKHSA also says drug-resistant strains are an increasing concern, and THT says a strain of extremely antibiotic-resistant shigella has been on the rise in the UK.

How can you make rimming safer?

For hepatitis A and B, the NHS says vaccination is the best way to prevent infection. Beyond that, use a barrier, wash first, wash your hands after sex, skip rimming while either of you has sores or a stomach bug, and test regularly, because the NHS says many STIs have no symptoms.

1. Get vaccinated if you're at high risk. The NHS says you only need the hepatitis A vaccine if you're at high risk, and adults only need the hepatitis B vaccine if they're at high risk. Its examples include men who have sex with men for both, and people with multiple sexual partners for hepatitis B. The HPV vaccine, which protects against genital warts, is also offered to men up to and including 45 years old who have sex with men, some trans men and trans women, sex workers and people living with HIV.
2. Use a barrier. A dental dam is a small, thin, square piece of latex that sits between the mouth and the anus during oral sex. THT suggests a condom cut into a square as a barrier, and the NHS says condoms are free from sexual health clinics and some GP surgeries and pharmacies. Sheffield's NHS sexual health service advises checking the dam for holes or tears, using a water-based lubricant (oil-based ones can break down latex, so the dam can leak or tear), not licking the side that has touched the anus, and never using a dam twice.
3. Wash first. Brook suggests gently washing the area with water and gentle soap before any kind of anal sex. It also warns that douching (washing inside the anus with water) can wash away healthy bacteria and protective mucus, and can damage the delicate lining if done incorrectly. Our guide on how to prepare for anal sex has more.
4. Wash your hands after sex, and shower if you can. UKHSA and THT both advise this to cut the spread of shigella, and THT says showering after sex is even better than washing.
5. Skip it when there are sores or cuts. Brook advises against oral sex if there are open sores or cuts on the mouth, anus or genitals. The NHS advises avoiding oral and anal sex while either of you has herpes blisters or sores, or the tingle or itch that means an outbreak is coming.
6. Wait out a stomach bug. UKHSA says someone with shigella can stay infectious for up to a month, even after they start to feel better, and advises keeping up hygiene precautions throughout recovery and avoiding sexual contact until they've been free of symptoms for at least 48 hours. THT's advice is to avoid sex until a week after symptoms stop.
7. Test regularly. Brook advises getting tested for STIs regularly and each time you have sex with a new partner. If you get a stomach upset after sex, THT suggests telling the GP or clinic that you may have picked it up from sex, possibly shigella, so they know which tests to give you.

Is it safe to switch from rimming to vaginal sex?

Use a fresh barrier and clean hands first. Brook advises washing your hands if you've touched the anus and using a new condom before vaginal sex, because bacteria moved from the anus to the vagina could cause a urinary infection. Sheffield's NHS sexual health service says to use a new dental dam when switching between oral-anal and oral-vaginal sex.

The NHS explains why: urinary tract infections (UTIs) are usually caused by bacteria from poo entering the urinary tract, and women have a shorter urethra than men, so bacteria are more likely to reach the bladder or kidneys. Its tips to prevent UTIs include washing the skin around the vagina with water before and after sex and peeing as soon as possible after sex.

If you're pregnant and think you've been exposed to hepatitis A, THT advises discussing testing with your doctor or midwife, because hepatitis A in pregnancy can increase the likelihood of a miscarriage or a premature birth.

What are the symptoms of an infection after rimming?

Shigella shows up quickly. UKHSA says symptoms typically begin 1 to 3 days after exposure, though it can take up to a week to feel unwell, and the most common are diarrhoea (which can be bloody), stomach cramps, fever, nausea and vomiting. Most people recover within 4 to 5 days, but the illness can last up to 2 weeks.

Hepatitis A can take longer: THT says symptoms can appear up to six weeks after infection. The NHS lists symptoms including a high temperature, flu-like symptoms, feeling sick, pain in your upper tummy, pale poo, dark pee, itchy skin and yellowing of the skin and eyes (jaundice). Some adults have mild symptoms or none.

Many STIs cause no symptoms at all. When they do, the NHS lists signs such as an unusual discharge from the vagina, penis or anus, pain when peeing, lumps or skin growths around the genitals or bottom, a rash, unusual vaginal bleeding, itchy genitals or anus, and blisters, sores or warts around the genitals or anus.

When should you get help?

• Go to a sexual health clinic if you think you may have an STI, a partner has symptoms of one, or you're worried after sex without a condom or dental dam. The NHS says sexual health clinics are free and confidential, and you don't usually need a GP referral, though it's worth contacting the clinic first.
• Contact your GP if you think you have shigella, or visit a sexual health clinic if you may have caught it through sex, UKHSA says. Ask for an urgent GP appointment or get help from NHS 111 if you have bloody diarrhoea.
• See a GP if you have symptoms of hepatitis A and you're a man who has sex with men, or you've recently been in close contact with someone who has it. Ask for an urgent GP appointment or get help from NHS 111 if you think you might have hepatitis A and you're pregnant, aged over 60 or have a liver condition.

The NHS says clinic staff are there to help, so try not to feel uncomfortable talking about your sex life, and you don't need to give your real name.

For the wider basics, see our anal sex safety guide, our page on anal warts and other infections around the bottom and our pegging safety guide.