Many sexually active people assume that sexually transmitted infections (STIs) only affect the genital area. While symptoms such as genital warts, unusual discharge, lesions, and furrows may prompt a visit to a sexual health clinic, STDs can also present with lesser-known symptoms.
Although it may surprise some people, diarrhea can be a common sign of an STD.
If you’re experiencing diarrhea and think an STD may be causing it, keep reading to learn more.
Worried about an STD? Try it with Better2Know.
What is diarrhea?
Diarrhea is loose, watery and frequent passage of stool that can often be accompanied by other symptoms, such as:
- Pain in the lower abdomen
- Inflation
- Nausea
- Vomiting
- Fever
- Bloody stools
- Mucus in the stool
- Urgent need to defecate
Acute diarrhea
Most cases of diarrhea are acute. In these cases, diarrhea results from your body’s response to certain foods, viruses, bacteria, and other foreign agents.
Common causes of diarrhea include:
- Viral infections (flu, norovirus, rotavirus, etc.)
- Bacterial infections (e.coli, do. I’m having a hard timeetc)
- Medicines, including many antibiotics and antiviral medicines
- Fructose, which can be found in many fruits and honey
- Artificial sweeteners
These cases of diarrhea are usually temporary and go away once the underlying cause is corrected (ie, the infection clears or heals, or any foods you eat change).
Chronic diarrhea
Chronic diarrhea, often caused by digestive disorders, may require treatment or lifestyle changes. Chronic diarrhea is a common symptom:
- Irritable Bowel Syndrome (IBS)
- Crohn’s disease
- Pancreatitis
- Colitis
- Food intolerances
Are there STDs that cause diarrhea?
While many people may not associate diarrhea with sexually transmitted infections, it can be a more common symptom than you might think.
Here are some infections that can cause or be associated with diarrhea.
HIV
Human immunodeficiency virus (HIV) it damages the immune system by compromising your body’s ability to produce T-cells. If left untreated, HIV can progress slowly over several years and develop into AIDS.
Diarrhea is one of the most common symptoms of HIV infection. The severity of diarrhea can vary from person to person. It can occur during an acute HIV infection in the first days and weeks. Other symptoms of an acute HIV infection include:
- Fever
- Nausea
- Night sweats
- Headaches
- Joint pain
- Sore throat
- Swollen lymph nodes
Diarrhea can also be caused by HIV medications. Antiretroviral drugs, which are often used to treat HIV, often carry a risk of diarrhea.
People with HIV also often experience gastrointestinal problems, resulting from a weakened immune system. Common gastrointestinal problems during HIV include:
- Intestinal infections, such as:
- Bacterial overgrowth within the digestive tract
- HIV enteropathy
Gonorrhea
Gonorrhea is a bacterial STD transmitted through unprotected vaginal, anal, or oral sex.
While gonorrhea infections are more common in the genital area, you are likely to get the infection in your rectum. This usually results from unprotected anal sex and sharing sex toys.
People with rectal gonorrhea infection may experience proctitisan inflammation of the rectum associated with pain and itching around the anus, painful bowel movements and unusual rectal discharge.
Although gonorrhea does not cause watery stools, it can cause symptoms that often occur alongside diarrhea, including blood and mucus in the stool and an urgent need to pass stool.
Chlamydia
Like gonorrhea, you can also get a Chlamydia infection in your rectum, also through unprotected anal sex and sharing sex toys.
A chlamydia infection in the rectum can lead to similar symptoms proctitisincluding inflammation and pain around the rectum, painful bowel movements and unusual discharge from the anus.
As with gonorrhea, chlamydia is unlikely to cause watery stools. However, it will cause the same irritation and urgency to defecate.
Syphilis
Although they are very rare, they have existed reported cases of Syphilis causing lower gastrointestinal symptoms such as diarrhoea, where syphilis spirochetes have been found in the gastrointestinal tract of infected individuals.
These cases usually occur in men who have sex with men and trans women who have anal sex. In many of these cases, the gastrointestinal problems were attributed to conditions such as inflammatory bowel disease, allowing the infection to progress and harm the patient’s health.
Although diarrhea is not normally caused by syphilis, including a syphilis test in an STD screen would be prudent for those concerned.
Herpes
As with the above examples, taking anal Herpes Infection in your rectum can lead to diarrhea in some cases.
HSV colitis is a rare but serious complication of inflammatory bowel syndrome (IBS). Immunosuppressive drugs are often used to treat IBS, and reduced immune function can leave some patients at risk of developing opportunistic infections.
An HSV infection of the anus contracted by someone with IBS can worsen gastrointestinal symptoms, causing watery stools, blood in the stools, abdominal pain, fever and nausea.
How do you know if an STD is causing your diarrhea?
Having diarrhea does not necessarily mean you have an STD. Because of the complexity of these infections, diagnosing an STD based on a single symptom is nearly impossible.
However, if you experience diarrhea, it may indicate an STD. In such cases, the examination is necessary to ensure your health and well-being.
Final thoughts
Get tested for HIV, chlamydia, gonorrhea, syphilis and herpes with Better2Know. Book a test at a sexual health clinic near you or try from the comfort of your own home with the wide range Home test kit.

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