10 Causes of Hot Flashes and How to Find Relief

Hot flashes are thought to occur when a drop in estrogen (or changes in other hormones) disrupts the body’s natural thermostat, known as the hypothalamus. Also known as vasomotor symptoms (VMS), hot flashes are commonly associated with menopause but can also be caused by medication side effects, thyroid or pituitary problems, and certain cancers or cancer treatments.

1. Menopause

Hot flashes are one of the most common symptoms of menopause. In fact, more than 80% of people experience hot flashes during menopause, generally when menopause first starts.

Hot flashes during menopause occur because of a drop in estrogen levels. Estrogen affects the brain and, along with testosterone, helps regulate the hypothalamus, which serves as the body’s thermostat.

When estrogen decreases, the hormone imbalance makes the hypothalamus perceive the body as hotter than it is. In response, the hypothalamus activates sweat glands, increases heart rate, and widens blood vessels near the skin’s surface to help cool the body.

The sudden flush of heat usually starts in the face or chest and can spread throughout the entire body. Episodes tend to start abruptly and can last anywhere from a few seconds to up to 30 minutes.

When hot flashes occur at night, they are commonly referred to as night sweats.

While anyone going through menopause can experience hot flashes, certain factors can influence their likelihood, frequency, or severity, including:

• Older age (typically more frequent and severe after 50 years)
• Cigarette smoking (past or current)
• Current depression
• A history of oral contraceptive use

2. Prescription Drugs

If you’re experiencing hot flashes, it could be because of a medication you are taking. Some drugs directly affect the balance of estrogen in the body. Others interfere with a system known as the hypothalamus–pituitary–adrenal (HPA) axis.

The HPA axis coordinates communication between the hypothalamus and the hormone-producing pituitary and adrenal glands. By continuously sending and receiving chemical messages, the HPA axis adjusts hormone levels to maintain equilibrium in the body, including body temperature.

If the chemical messages are in any way disrupted, vasomotor symptoms can occur.

Medications that may cause hot flashes include:

3. Hyperthyroidism

Hyperthyroidism (overactive thyroid gland) can also cause vasomotor symptoms. The thyroid gland also interacts with the hypothalamus and pituitary gland to ensure that the right amount of thyroid hormones is produced.

The hypothalamus sends signals “telling” the pituitary gland when to produce thyroid-stimulating hormone (TSH), which in turn tells the thyroid gland when to start producing thyroid hormones like thyroxine. When enough thyroid hormones are produced, the hypothalamus “turns off” the pituitary gland until more thyroid hormones are needed.

When the thyroid gland is overactive, it can disrupt this loop and overstimulate the hypothalamus, leading to vasomotor symptoms.

4. Hypogonadism

It is possible for males and females to experience hot flashes as a result of hypogonadism (low testosterone). This is because hypogonadism can lead to estrogen deficiency.

Under normal circumstances, a small proportion of testosterone in the body is converted into estrogen. If testosterone levels are low, estrogen levels can also drop. If estrogen levels are exceptionally low, hot flashes can occur.

People with prostate cancer sometimes undergo androgen deprivation therapy to block the production of testosterone that can otherwise fuel the growth of the cancerous tumor. Doing so can trigger hot flashes in three out of four people undergoing deprivation therapy, according to one study.

5. Anxiety and Stress

Anxiety disorders can cause somatic (physical) symptoms like hot flashes, a racing heartbeat, and increased sweating. This is common in people who have panic attacks or post-traumatic stress disorder (PTSD).

During periods of extreme anxiety, the body releases a hormone called cortisol that triggers the “fight-or-flight” response to better cope with the perceived threat.

Among other things, cortisol causes your heart rate and respiration rate to increase to supply more oxygen to muscles. These and other physiological responses can cause the body to spontaneously overheat, leading to hot flashes.

6. Cancer

In some cases, hot flashes can be caused by certain cancers or cancer treatments.

Though rare, hot flashes can be caused by carcinoid syndrome, a condition in which a carcinoid tumor secretes excessive hormones. A common symptom of carcinoid syndrome is flushing, mainly affecting the face, neck, or upper chest.

Flushing with carcinoid syndrome happens when excessive amounts of the hormone serotonin are released. The sudden surge in serotonin triggers a chain of events that causes the widening of blood vessels (vasodilation) and a surge in blood flow under the skin.

Other cancers that can cause hot flashes include:

Some cancer treatments can also cause hot flashes. These include surgery to remove the ovaries or testicles, chemotherapy, hormone treatment, and certain medications.

7. Infection

Any infection that causes a fever can trigger hot flashes. The body’s temperature can rise as it tries to kill off a viral or bacterial infection. If an infection is the cause of your hot flashes, you may also experience other symptoms such as fatigue, joint aches, and sweating.

There is a wide range of infections that could cause hot flashes, including:

8. Neurological Disorders

Hot flashes may also be the result of certain neurological disorders (conditions that affect the brain, nerves, and spinal cord). Sometimes, these conditions can interfere with the autonomic nervous system, which helps keep the body’s temperature in check.

For example, people with migraines often experience a feeling of extreme, sudden heat with sweating during the migraine attack.

Other neurologic disorders like Parkinson’s disease and multiple sclerosis (MS) can also prompt symptoms like excessive sweating, sudden body temperature shifts, and skin flushing.

9. Diet

Your diet also has the potential to cause hot flashes.

Alcoholic beverages can cause an abnormal response in some people that leads to blood vessel dilation and facial flushing. The phenomenon is a type of aldehyde dehydrogenase deficiency (alcohol intolerance) caused by a gene mutation common in people of East Asian descent.

Foods that contain nitrites, used in processed foods like hot dogs and deli meats, can have a similar effect on some people. The response is thought to be related to a nitrite intolerance rather than a nitrite allergy.

10. Rosacea

Rosacea is a skin condition characterized by redness and/or bumps on the face along with chronic facial flushing. The condition involves vasomotor instability (constricting or widening of blood vessels) mainly affecting the forehead, cheek, nose, and skin around the eyes and mouth. Rosacea tends to start in childhood as common facial flushing, often in response to stress.

People with rosacea are encouraged to avoid triggers like hot environments, spicy foods, hot beverages, alcohol, stress, and any medications that cause vasodilation.

How Are Hot Flashes Treated?

While there isn’t a cure for hot flashes, there are some ways to relieve the discomfort they can cause. The treatment will vary based on the underlying cause.

Medical Treatment

It’s important to seek a thorough diagnosis to pinpoint the exact cause of your hot flashes. This is especially true if you have symptoms of carcinoid syndrome, severe infections, hyperthyroidism, or anxiety disorders.

In some cases, prescription medications might help ease hot flashes, including:

A procedure called stellate ganglion block may be used to treat moderate to severe hot flashes by injecting an anesthetic into a nerve cluster in your neck. It’s typically used to treat those who haven’t responded to more conservative treatments. However, more research is needed to confirm its benefits and long-term effects.

Lifestyle Changes

If you are dealing with frequent hot flashes, consider making some of the following changes to help ease your discomfort:

• Wear lighter, breathable clothing.
• Use a fan or air conditioner when conditions are warm.
• Stay well hydrated, drinking around eight 8-ounce cups of water per day (or more when overheated).
• Reduce stress levels with mind-body therapies like deep breathing or meditation.
• Avoid alcohol, spicy foods, and excess caffeine.
• Quit smoking.

Talk to your doctor before making any dietary or medication changes, such as cutting back on caffeine, niacin supplements, or OTC fever reducers. The abrupt change in any habit may also trigger vasomotor symptoms.

When to See a Healthcare Provider

While most reasons for hot flashes are not serious, you do need to know what is causing them.

Try keeping track of the episodes. List the details about the outdoor and room temperature at the time that you had a hot flash, your diet and activity levels, and any medications that you used. In time, you and your healthcare provider may be able to pinpoint the problem.

See your healthcare provider if you have one or more of these symptoms along with hot flashes:

• They are suddenly becoming more frequent or getting worse.
• They are happening with symptoms of an allergic reaction.
• They are causing you stress and anxiety or interfering with your everyday life.