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Low Blood Pressure (cont.)

Micturition Syncope (Fainting During Urination or Bowel Movements)

One of the most common causes of syncope, (passing out or fainting), occurs when a person strains to urinate or have a bowel movement. This stimulates the vagus nerve, increasing acetylcholine in the body and dilating blood vessels, causing blood pressure to fall and decreasing blood supply to the brain. Though it is frightening and may result in a fall, micturition syncope is self-limiting, resolves quickly, and may need little treatment.

Medically Reviewed by a Doctor on 5/21/2014

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