Sexually transmitted infections (STIs) can spread as a result of having close physical contact with another person. They usually spread through vaginal, anal, and oral sex.

Oral sex carries a risk of contracting and transmitting certain STIs. Oral sex includes fellatio (oral sex on a penis), cunnilingus (oral sex on a vulva), and rimming (oral sex on an anus).

This article will discuss which STIs can spread through oral sex, how to prevent them, their symptoms, and when to see a doctor.

A homosexual male couple discusses safe sex in an image to accompany the article Oral sex STI risk charts: Transmission and prevention.Share on Pinterest
Image credit: blackCAT/Getty Images

According to the Centers for Disease Control and Prevention (CDC), the following STIs can spread through oral sex.

STIAreas of infectionHow it spreads
chlamydiathroat

genitals

urinary tract

rectum
Giving oral sex to a partner with chlamydia that affects their penis, vagina, urinary tract, or rectum may result in infection of the throat.

Receiving oral sex from a partner with chlamydia in their throat may result in infection of the penis, vagina, urinary tract, or rectum.
gonorrheathroat

genitals

urinary tract

rectum
Giving oral sex to a partner with gonorrhea affecting their penis, vagina, urinary tract, or rectum may result in infection of the throat.

Receiving oral sex from a partner with gonorrhea in their throat may result in infection of the penis, vagina, urinary tract, or rectum.
syphilislips

mouth

throat

genitals

anus

rectum
Giving oral sex to a partner with a syphilis sore or rash on their genitals or anus may result in infection of the lips, mouth, or throat.

Receiving oral sex from a partner with a syphilis sore or rash on their lips, mouth, or throat may result in infection of the genitals, anus, or rectum.
herpeslips

mouth

throat

genitals and surrounding areas

anus

rectum

buttocks
Giving oral sex to a partner with herpes that affects their genital area, anus, rectum, or buttocks may result in infection of the lips, mouth, and throat.

Receiving oral sex from a partner with herpes on the lips, mouth, or throat may result in infection of the genital area, anus, buttocks, or rectum.
human papillomavirus (HPV)mouth

throat

genital area

penis

vagina

cervix

anus

rectum
Giving oral sex to a partner with HPV on their penis, vagina, anus, or genital area may result in infection of the throat.

Receiving oral sex from a partner with HPV in their throat may result in infection of the penis, vagina, anus, rectum, or genital area.
HIVimmune systemGiving oral sex on the penis, vagina, or anus of a partner with HIV may result in HIV infection.

Receiving oral sex on the penis, vagina, or anus from a partner with HIV may result in HIV infection.

There are several ways to prevent or reduce the risk of transmitting and contracting STIs. The sections below will discuss these in more detail.

Condoms

Condoms that cover the penis are a common type of barrier method of contraception.

There are three kinds of condom material. They can either be latex, plastic, or lambskin. Lambskin condoms can only help prevent pregnancy, not STIs.

Latex and plastic condoms protect against STIs by covering the penis and stopping it from coming into direct contact with the vagina or anus.

People should use a new condom whenever they start a different sexual activity. For example, a person should change their condom if they go from oral sex to anal sex. The same is true if they go from anal sex to vaginal sex.

Internal condoms

Internal condoms, or female condoms, are an alternative to the typical condoms that go over the penis. They provide the same amount of protection from STIs.

These condoms are plastic pouches that go inside the vagina or anus and cover some parts of the vulva and skin around the anus. This reduces a person’s risk of coming into contact with semen or skin that can spread STIs.

Dental dams

Dental dams are small latex or polyurethane sheets that act as a barrier between the mouth and the vagina or anus during oral sex. These limit the amount of contact between the mouth and the genitals or anus, reducing the risk of contracting an STI.

If a dental dam is not available, it is possible to cut a latex or plastic condom in half and use that as a dental dam instead.

HPV vaccine

HPV is a very common STI. Certain types of HPV can result in cancer and genital warts.

However, scientists have developed a vaccine that protects people against HPV. The vaccine is available to everyone aged 9–45 years. It is best to vaccinate children before they become sexually active to reduce the risk of them contracting an STI in adulthood.

This vaccine is safe. The most common side effects are temporary pain and skin flushing at the site of the injection.

The vaccine can only prevent HPV. It cannot cure or treat strains of HPV that a person already has before they receive the vaccination.

Preexposure prophylaxis

Preexposure prophylaxis (PrEP), which takes the form of a daily pill, helps reduce a person’s risk of contracting HIV. In fact, if a person takes PrEP every day, it can lower their risk of contracting HIV from sex by more than 90%.

People at high risk of contracting HIV from sex may benefit from taking PrEP. A person may be suitable for PrEP if they:

  • do not regularly use condoms
  • have a sexual partner who has HIV
  • have a sexual partner who is at high risk of having HIV
  • have anal or vaginal sex with many partners, especially without the use of condoms
  • have recently had another STI, such as chlamydia or gonorrhea
  • do sex work that includes vaginal or anal sex
  • have used injected drugs, shared needles, or had treatment for drug use within the past 6 months

STISymptomsComplications
chlamydiaMany people do not have any symptoms, but if they do occur, they may include:

a sore throat

discharge from the vagina or penis that may be bloody

a burning sensation when urinating

pain and swelling of the testicles

pain and discharge from the rectum
pelvic inflammatory disease, which may lead to pelvic pain, infertility, or non-viable pregnancies

premature births or low birth weights (in babies born from a person with chlamydia)

a chlamydia infection of the eyes or respiratory tract (in babies born from a person with chlamydia)

pain and scarring of the ducts attached to the testicles

a higher risk of contracting and transmitting STIs

arthritis, conjunctivitis, and a rash on the soles of the feet
gonorrheaMost people will not experience any symptoms, but if symptoms do occur, they may include:

discharge from the vagina or penis that may be bloody

a burning sensation when urinating

painful and swollen testicles

pain and discharge from the rectum
pelvic inflammatory disease, which may lead to pelvic pain, infertility, and non-viable pregnancies

premature births or low birth weights (in babies born from a person with gonorrhea)

blindness, joint infections, or blood infections (in babies born from a person with gonorrhea)

pain and scarring to the ducts attached to the testicles

a higher risk of contracting and transmitting HIV

skin sores and joint pain, which may spread to the heart and potentially lead to death
syphilisSome people have no symptoms, but some of the most common include:

painless ulcers or sores on the lips, mouth, throat, skin, or genital or anal regions

a rash on the torso, palms of the hands, or soles of the feet

flu-like symptoms
a higher risk of stillbirths (without treatment)

developmental delay, seizures, or death (in babies born from a person with syphilis)

a higher risk of contracting and transmitting HIV

muscle weakness and damage to internal organs

blindness, dementia, and death
herpesSome people have no symptoms, but if symptoms do occur, they may include:

headache or fever

painful or itchy sores around the site of infection
a higher risk of contracting and transmitting HIV

brain damage, internal organ damage, or death (in babies born from a person with herpes)
HPVSome people have no symptoms, but if they do occur, they may include:

warts in the throat that may cause changes in voice, difficulty speaking, or shortness of breath

genital or anal warts
cervical, anal, penile, head, and neck cancers (without treatment)
HIVSymptoms may not appear for several years, but when they do, they may resemble flu-like symptoms.a higher risk of contracting infections and developing cancer (due to being immunocompromised)

Most people will not experience any symptoms of STIs.

Therefore, it is very important that a person undergoes testing if they believe that they are at risk of having an STI.

This may be the case if they are engaging in unprotected sex, have a partner with an STI, or experience any symptoms — such as discharge — that are unusual for them.

People can undergo testing at a doctor’s office, a health clinic, or their local Planned Parenthood.

Some people’s health insurance may cover all or part of the costs associated with testing.

Most STIs are treatable. A medical professional can talk a person through the treatment and management of any STIs they may have.

Oral sex comes with a risk of contracting or transmitting STIs, just like any other sexual activity with a partner.

Some of the more common STIs include chlamydia, gonorrhea, herpes, and HPV.

People can prevent the spread of STIs by using a barrier method of contraception, such as a condom, and vaccinating against HPV. If a person is at high risk of contracting HIV, they may consider taking PrEP.

Most people do not experience any symptoms of STIs, but each infection can cause lifelong and harmful complications if a person does not seek treatment.

For this reason, it is important for people to undergo regular testing for STIs.