Why Do People Get Boners When They Poop?

Blood can flow to the penis and rectum as the body pushes during a bowel movement. As a result, an erection while pooping is possible, Jesse Mills, MD, an associate clinical professor of urology and director of The Men's Clinic at the University of California, Los Angeles, told Health.

That might not be something you've been losing sleep over, but many people are asking about it thanks to a viral post that claimed it's true. In a 2020 TikTok video with over 2.3 million views, user Brandon Ball gave a thumbs up with the caption, "Wait til girls find out that guys get bonners (sic) when they poop."

So, why do people get boners when they poop? There are several reasons, including the time of day and prostate gland stimulation. In some cases, getting an erection is simply a coincidence. 

Why Can Erections While Pooping Occur?

According to Dr. Mills, getting a boner while pooping is a "vascular phenomenon." The vascular, or circulatory, system consists of vessels that carry blood and fluid, deliver oxygen and nutrients to body tissues, and remove tissue waste matter.

The internal pudendal artery supplies blood to the penis. An erection happens if the internal pudendal artery dilates, increasing blood flow to tissues in the penis. As a result, the penis becomes rigid. A bowel movement can apply enough pressure to increase blood flow to the penis, noted Dr. Mills.

"Anatomically speaking, there is no reason a person can't have an erection and a bowel movement at the same time," Mike Bohl MD, MPH, director of medical content and education at Ro, told Health.

Having an erection while pooping may also involve the parasympathetic nervous system. The parasympathetic nervous system, known as the "feed and breed" system, controls sexual arousal, digestion, and excretion.

Possible Causes of an Erection While Pooping

A few possible causes may contribute to having an erection during a bowel movement, such as:

• The time of day: If you have a bowel movement after waking up in the morning, an erection may occur. An active parasympathetic nervous system causes nocturnal penile tumescence, known as "morning wood." The average person with a penis has about three to five erections nightly.
• The number of bowel movements: The number of daily or weekly bowel movements may also affect whether an erection occurs. The average person has one to three bowel movements daily. So, if you go multiple times daily, the chance of having a boner while pooping is more likely, noted Dr. Bohl.
• Coincidence: Beyond timing, getting a boner at the same time as pooping can simply be a coincidence. For example, having arousing thoughts during a bowel movement can result in an erection, said Dr. Bohl.
• Prostate gland stimulation: Also, some people may find having a bowel movement arousing. Inside the body, the prostate gland is close to the rectum. A bowel movement may apply pressure to the prostate gland, which can be pleasurable for some men.
• Coprophilia: Also, having an erection while pooping might be related to a sexual fetish centered around feces, called coprophilia, noted Dr. Bohl. 

Is It Dangerous To Get an Erection While Pooping?

Having an erection while pooping isn't dangerous, nor is it clinically significant. In other words, if it happens to you, there's no need to make an appointment with a healthcare provider. An occasional boner while pooping is just one of those things the human body can do.

"However, if it's interfering with your daily life, you should speak to a healthcare provider," suggested Dr. Bohl.

A Quick Review

Having a boner while pooping is normal and may happen for several reasons. Going to the bathroom in the morning, stimulating the prostate gland, or having arousing thoughts while pooping can cause an erection. However, if having an erection while pooping interferes with your daily life, consult a healthcare provider.