A hot flash is the sudden feeling of warmth in the upper body, which is usually most intense over the face, neck and chest. Your skin might redden, as if you're blushing. A hot flash can also cause sweating. If you lose too much body heat, you might feel chilled afterward. Night sweats are hot flashes that happen at night, and they may disrupt your sleep.
Although other medical conditions can cause them, hot flashes most commonly are due to menopause the time when menstrual periods become irregular and eventually stop. In fact, hot flashes are the most common symptom of the menopausal transition.
