Common types of UC include: 1  proctosigmoiditis, which affects the rectum and lower portion of the colon. 2  left-sided colitis, which affects the left side of the colon beginning at the rectum.  total colitis, which affects the entire large intestine.
Vasovagal syncope. Vasovagal syncope is a sudden loss of consciousness mediated by the vagus nerve. It occurs when the vagus nerve is overreactive to certain triggers, such as the sight of blood or extreme emotional distress, and causes a sudden drop in blood pressure.
Sometimes there is no classical vasovagal syncope trigger, but common triggers include: Standing for long periods of time; Heat exposure; Seeing blood; Having blood drawn; Fear of bodily injury; Straining, such as to have a bowel movement; Prevention. You may not always be able to avoid a vasovagal syncope episode.