Situational syncope occurs in specific scenarios and can be triggered by a variety of situations such as having blood drawn, straining during urination or bowel movements, and coughing. Emotional stress, fear, or pain can also provoke this reaction. Prior to fainting, individuals often experience paleness, nausea, sweating, and weakness. This condition is caused by a reflex of the autonomic nervous system known as the vasovagal response. This reflex causes the heart rate to decrease (bradycardia) and the blood vessels in the legs to dilate (expand). Consequently, the heart pumps less blood, blood pressure falls, and blood tends to pool in the legs rather than reaching the brain. This deprivation of oxygen to the brain results in a fainting episode. Situational syncope is also referred to as vasovagal syncope. For more information, see syncope and vasovagal reaction.
