Symptoms
Hot flashes are commonly identified by a sudden feeling of intense heat in the upper body and face. Hot flashes can also involve sweating, a rapid heartbeat, anxiety, weakness, a headache, dizziness, or feeling as though you are about to suffocate. These other symptoms might occur at the same time as the hot flash or might precede it by a few minutes. Some women will have an uneasy feeling, called an aura, just before the hot flash that lets them know that it is coming. Hot flashes are usually followed by flushing, causing reddening of the face and upper body. The intensity of hot flashes can range from a relatively mild feeling of warmth to an episode that leaves you sweaty.
Causes
Hot flashes can be a result of sudden changes in hormone levels in a female, which commonly occur during menopause. According to breastcancer.org, 85 percent of women going through menopause experience hot flashes as menopause approaches and during the first one or two years after menstrual periods cease. Although hot flashes are commonly attributed to low estrogen levels, the Mayo Clinic notes that low estrogen levels, on their own, are not able to cause hot flashes, but rather it is the withdrawal of estrogen that seems to trigger the hot flashes. These decreasing estrogen levels are most commonly caused by menopause, but they can also be caused by some medications.
Mechanism
According to breastcancer.org, hot flashes occur as a result of the effect that decreasing estrogen levels have on a part of the brain called the hypothalamus. The hypothalamus controls many bodily functions, including appetite, sleep schedule and body temperature. Decreasing estrogen levels cause the hypothalamus to believe that the body's temperature is too hot, causing it to send out signals to the rest of the body to try and relieve this excess heat. As a result, epinephrine (also known as adrenaline) gets released, which causes the heart to beat faster, the blood vessels to dilate and expand to let off heat, and the sweat glands to become activated. All of these effects contribute to the symptoms of a hot flash.
