It is possible to get a sexually transmitted infection (STI) from oral sex. Some STIs, such as genital herpes and gonorrhea, develop more commonly from oral sex than other STIs.

Worldwide, about 1 million new STIs are acquired each day, according to the World Health Organization (WHO). It is essential that sexually active people understand how STIs are transmitted and how they can reduce the risk of spreading infections.

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Many STIs may be spread through oral sex.

It is possible to contract many STIs through oral sex, as oral sex involves close contact and often an exchange of bodily fluids.

STIs spread through contact with bodily fluids or skin containing the STI. Different STIs spread at different rates and through various bodily fluids. The chances of getting an STI depend on a variety of factors.

The STIs most frequently spread through oral sex include:

Genital herpes

Genital herpes is a virus that is transmitted through vaginal, oral, or anal contact with someone who has herpes. It is highly contagious and tends to be more contagious during an active outbreak.

The primary symptom of herpes is the appearance of blister-like sores on or around the genitals. The sores may spread to the thighs, buttocks, or other nearby regions. They may also affect the mouth, tongue, and lips, depending on the type of herpes.

Even condoms and other barrier protection methods may not prevent the virus from spreading. This is particularly so if someone has a sore or a blister that is not completely covered by a condom or dental dam.

People who have oral herpes may also spread the herpes infection to the genitals of their sexual partners through oral sex.

It is possible for a person to have herpes for many years without having an outbreak of sores. Even people who have only ever had one outbreak, or who have no symptoms but have never been tested, may have herpes.

Herpes is not curable, but medications can manage symptoms.


Gonorrhea is a highly contagious bacterial infection that spreads through sexual contact with the vagina, penis, anus, or mouth of a person with the disease.

Many people who have gonorrhea do not have any symptoms at all. When symptoms do appear, they may include:

  • genital discharge
  • painful bowel movements
  • itching or burning during urination
  • white, green, or yellow discharge from the penis
  • bleeding between periods

Gonorrhea is treatable, but it can cause serious complications if left untreated. In women, untreated gonorrhea can cause a condition called pelvic inflammatory disease. This syndrome may lead to infertility. Less frequently, gonorrhea may also cause infertility in men.


Syphilis is a bacterial infection that spreads through vaginal, oral, penile, anal, or skin contact with syphilis sores. The sores may be small or unnoticeable, so the only way for a person to know for sure whether they have syphilis is to get tested.

Syphilis is treatable, but if it is left untreated, it can cause organ failure, dementia, and other serious health problems.

In its earliest stage, syphilis presents as many small, blister-like sores. The sores appear where syphilis entered the body, so people who get syphilis from oral sex may have sores on their genitals or near their mouth.

As syphilis develops, it causes rashes and harms the mucous membranes. In later stages, it can cause serious problems in many organs, including the heart and brain.

Other conditions

Other infections are less likely to spread through oral sex, though infection is still possible.

These include:

  • HIV, which is transmitted when bodily fluids containing the infection come into direct contact with another person’s bloodstream. In its earliest stages, HIV may not cause any symptoms. Over time, the disease weakens the immune system.
  • Chlamydia, which spreads through vaginal, oral, penile, or anal contact with a person who has the infection. Most people do not have symptoms. For those who do, genital itching or burning may occur, along with difficulty or pain urinating.
  • Pubic lice, which are tiny insects that feed on the blood and live in the pubic hair. The insects can also live on other body hair, but not on the scalp. Pubic lice can jump from one person to another through physical contact.
  • Hepatitis B and C, which are viruses that attack the liver. They can spread through contact with bodily fluids containing the infection. Symptoms may begin with flu-like symptoms. In some people, the virus can cause acute liver failure or chronic liver problems.
  • Genital warts, which are lumps and bumps on or near the genitals caused by the human papillomavirus (HPV). The disease spreads when people come into physical contact with a genital wart. Many people with genital warts have no symptoms, though some have pain and itching near their genitals.
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HIV may spread through contact with open wounds or mucous membranes, including the vagina.

HIV is present in blood, breast milk, vaginal fluids, rectal fluids, semen, and pre-seminal fluid. To contract the disease, bodily fluids containing the infection must come into contact with another person’s bloodstream.

This can happen in three ways:

  • through contact with an open wound, even a tiny one
  • through contact with a mucous membrane, such as the vagina
  • through direct contact with the bloodstream, such as through sharing needles

Oral sex does not provide direct contact with the bloodstream. To get HIV from oral sex, the bodily fluids of a person with the infection would need to come into contact with a torn mucous membrane or wound on their sexual partner.

It is also possible to transmit the virus when the person giving oral sex has an open wound in their mouth or another area of the body that comes into contact with the recipient’s mucous membranes or an open wound.

AIDS, or acquired immune deficiency syndrome, is the name given to a condition in which a person’s immune function is absent due to a chronic HIV infection. AIDS can lead to a range of unusual infections and illnesses, but AIDS cannot be directly transmitted — a person will contract HIV first before developing AIDS.

How contagious a virus is may change over time or with treatment. In the case of HIV, for example, higher viral loads or higher quantities of the virus in the blood make the virus more contagious.

The only strategy that can eliminate the risk of transmitting oral STIs is avoiding all sexual activity, including oral, anal, and vaginal sex.

To reduce the risk while remaining sexually active, a person can:

  • getting tested regularly for STIs and asking all partners to do the same
  • considering a monogamous, committed relationship with a person who has been screened for STIs
  • using barrier methods, such as condoms or dental dams, to reduce the risk of transmission
  • avoiding sex with someone who has a visible outbreak of herpes, genital warts, pubic lice, or syphilis
  • treating any STIs quickly as prompt treatment can eliminate or reduce the risk of spreading the infection

Sexually active people should talk to a doctor about the risk of oral sex with a person who has the infection. In some cases, there are precautions a person can take to avoid contracting the infection.

In all cases, open communication with a partner and keeping up to date with reliable medical information can help people make wise decisions.