Fainting: Frightening, but seldom serious
Fainting occurs when something interrupts blood flow to the brain, causing a sudden, temporary loss of consciousness. Although usually harmless, fainting can cause injuries and sometimes signals a problem with the heart or circulatory system. Some faints result from a strong emotion (from getting bad news, for example) or excessive straining or coughing. Older people may faint because of low blood pressure when standing up, known as orthostatic hypotension. Other possible causes include a heart rate that’s either too fast or too slow, which may result from electrical abnormalities in the heart, thyroid problems, or certain medications.
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