What Causes Hot Flashes?

August 2018

by Nivin Todd, MD medicinenet.com

Doctors Call It Flushing
You may think of hot flashes — sudden waves of heat coming from your head, neck, or torso maybe with red, blotchy skin, sweating, and a rapid heartbeat — as something only women get around the time they stop having their period. But this flushing can be the result of many things as your body tries to cool down. Not everyone sweats when they have one, and you may feel chilled afterward.

Hormone Levels
This is what’s behind menopausal hot flashes. As the estrogen in her body declines, a woman’s thermostat resets and cooling measures start to kick in sooner. But a man might get hot flashes as his testosterone

level drops in middle age, especially if he’s had a certain kind of prostate cancer treatment. An overactive thyroid gland, perhaps from Graves’ disease or after giving birth, or something else that’s causing high levels of thyroid hormone may also do it.

Your body temperature naturally rises when you work hard. To keep up, your cells burn more fuel, which makes extra heat. Your body sends more blood closer to the skin to cool it off, and evaporating sweat helps bring your temperature down. That’s why it’s important to drink water when you work out. If you exercise regularly, your body gets used to that heat you make, and your core temperature can get a little higher before you react.

Your body fires up when it’s fighting germs. And that rising body temperature will trigger a part of your brain called the hypothalamus to start the cooling process and bring your temperature back to normal. Call your doctor if your fever is more than 103 or if you also have a bad headache, breathing problems, or can’t stop throwing up.

Allergic Reaction
A hot flash is common with a serious reaction called anaphylaxis as your immune system releases cells to try to fight off something that’s actually harmless. You’ll usually have other symptoms like stomach pain, hives, and breathing problems, too. And you need a shot of epinephrine — fast.

Neurological Disorders
Your autonomic nervous system controls things you don’t have to think about, like your breathing, heart rate, blood pressure, body temperature, and sweating. Anything that throws off how it works can cause flushing. That includes Parkinson’s disease, epilepsy, MS, and spinal injury and nerve damage.

Migraine and Cluster Headaches
These painful and sometimes disabling headaches can also mess with your autonomic nervous system. Your brain isn’t processing messages from the nerves in your head and neck about touch, pain, temperature, and vibration correctly. Your “fight or flight” response may kick in, which gets your blood pumping and widens your airways.

Flushing can be a side effect of many drugs. Some heart and blood pressure medicines, including calcium channel blockers and nitroglycerin, and ED prescriptions, like sildenafil (Viagra), tadalafil (Cialis), and vardenafil (Levitra), open up your blood vessels. High doses of steroids can affect your hormone balance. Chemotherapy drugs and painkillers from aspirin to opiates are also culprits.

Food and Additives
Your five-alarm, extra-spicy meal probably gets its kick from red peppers. They have capsaicin, which confuses your nervous system to react like you’re being burned.