Sometimes, we may strain ourselves to the point of physical collapse during a bowel movement. Known as defecation syncope, this occurs when a person passes out from pushing too hard while pooping. While little is known about the condition, cardiologist and syncope researcher Dr. Robert Sheldo told CTV News that defecation syncope accounts for up to 3% of his patients’ syncope cases.
The cause of defecation syncope is also thought to be related to the body’s vasovagal reaction, where excessive strain prompts a drop in heart rate and blood pressure and causes the person to lose consciousness. Those with certain pre-existing health conditions, such as hypotension, may be at an increased risk for defecation syncope. This was supported in an early 1986 research article published in JAMA Internal Medicine in which researchers examined 20 cases of defecation syncope. Nine patients were found to have medical issues, including gastrointestinal problems, heart disease, and stroke-like symptoms. While underlying health issues may play a role in cases of defecation syncope, no clear cause was found for 11 of the study participants.