It’s normal to feel hot and sweaty when you’re out in the summer sun, but heat intolerance can be a sign of some medical conditions. Find out what causes heat sensitivity.
Do you feel hot and sweaty even when everyone around you is comfortable? Have you developed a recent intolerance to heat? It may be more than just the hot weather. Certain medical conditions can increase a person’s sensitivity to heat even when temperatures are moderate. What conditions cause heat intolerance?
Medications: A Commonly Overlooked Cause of Heat Intolerance
If you have heat sensitivity and you’re on new medications, check with your doctor. Some drugs, particularly ones that are amphetamine based, can cause heat intolerance and sweating. Other medications that cause heat intolerance and easy sweating are drugs used to treat mood disorders such as anti-depressants and anti-psychotic drugs.
Certain types of pain killers can also cause sweating and heat sensitivity. Another drug that most people don’t think of that causes heat intolerance is caffeine. If you’re always hot and sweaty, cut back on caffeinated coffee and tea – and ask your doctor if your medications could be the cause.
A Common Cause of Heat Intolerance in Women
Most women are familiar with the hot flushes associated with menopause. This type of intolerance to heat comes on quickly and disappears as quickly as it came – only to recur again later. Hot flushes may start a few years before menopause and last several years after menstruation has stopped. Hormone replacement therapy helps, but isn’t necessarily a safe option due to the increased risk of breast cancer, stroke, and heart disease associated with taking them. Fortunately, this form of heat sensitivity eventually goes away in most women.
Another, not infrequent, cause of heat intolerance is an overactive thyroid – a condition known as hyperthyroidism. A person suffering from hyperthyroid may feel constantly warm and sweaty, and have other symptoms such as palpitations, weight loss, nervousness, tremors, muscle weakness, hair loss, and fatigue. Hyperthyroidism can usually be diagnosed using blood tests and treated with medications.
Other Causes of Intolerance to Heat
A variety of other conditions cause heat intolerance including multiple sclerosis, diabetes, heart failure, and certain types of infection. Tumors of the adrenal medulla called pheochromocytomas can cause sweating and intolerance to heat – although they’re rare.
The Bottom Line?
If you’re experiencing heat sensitivity or heat intolerance, see your doctor for a check-up and blood tests to make sure you don’t have an overactive thyroid or diabetes.
Merck Manual. Eighteenth edition.