The Science Behind Hot Flashes Due to Menopause

Few symptoms of menopause have gotten as much attention as hot flashes, and with good reason. Research suggests that nearly half of women going through menopause experience moderate to severe hot flashes and night sweats, making them a big distraction during this phase of life.

“I’ve spent almost two decades as a board-certified OB-GYN and I’ve seen that hot flashes can be quite bothersome and impactful to daily life for some women,” says Dr. Jennifer Ashton, a board-certified OB-GYN, nutritionist, and former network chief medical correspondent, and paid spokesperson for Astellas Pharma. “Some women report increases in irritability, feelings of fatigue, social embarrassment and isolation, especially when becoming flushed or sweating profusely. Some women even miss work as a result of menopausal hot flashes.”

Hot flashes can also interfere with sleeping, making it hard for many women to focus and function the next day, Dr. Ashton says. “Night sweats can also drench bedding, disturbing healthy sleep for both the person experiencing it and their partner,” she adds. 

Like many other things in life, hot flashes are complicated, and there’s a lot happening in the body beyond “just” sweating in any given moment. Here’s what all women need to know about what’s happening when you experience a hot flash, plus how to help manage them.

What happens in the body during a hot flash?

There are a few things going on at once during a hot flash. “When you’re having a hot flash during menopause, it’s because of what’s happening in your ovaries—specifically, your estrogen levels are starting to drop,” Dr. Ashton says. 

The brain also plays a role, she says. A brain chemical called neurokinin B (or NKB), that’s involved in the occurrence of hot flashes, gets thrown out of balance due to declining estrogen levels. “Normally, estrogen helps keep NKB balanced,” Dr. Ashton explains.

As estrogen levels drop, more NKB binds to receptors in the hypothalamus—the part of your brain that controls temperature, Dr. Ashton says. “When NKB binds to the receptor, like a docking port, in the hypothalamus during menopause, it triggers hot flashes and night sweats,” she says (Dr. Ashton points out that night sweats are simply hot flashes that happen at night).

Do all women have hot flashes in menopause?

All women don’t experience hot flashes the same way—or even have them at all. “Women’s experience with hot flashes due to menopause vary and while all women will experience a drop in estrogen during menopause, not all women will experience hot flashes,” Dr. Ashton says. 

Some women experience mild hot flashes, meaning they feel a sensation of heat without sweating, while others experience hot flashes that are moderate in severity, or a sensation of heat with sweating. Some women can have severe hot flashes that cause sweating and cause them to stop what they’re doing.   

Hot flashes also disproportionately impact women of color. In fact, one study found that 46% of Black women experienced hot flashes due to menopause, compared to 37% of White women. 

What treatment options do women have?

Dr. Ashton stresses that there are now more prescription treatment options than ever for moderate to severe hot flashes and night sweats due to menopause. She recommends speaking with your healthcare provider to learn more about potential treatments, including hormonal and non-hormonal options.

“For women who cannot or choose not to take hormones, VEOZAH™ (fezolinetant) may be an option, which is 100% hormone-free and the first treatment designed to block the binding of NKB in the temperature control center of the brain,” Dr. Ashton says. “VEOZAH is a once daily oral medication proven to reduce the number and severity of hot flashes day and night.” VEOZAH can cause serious side effects, including liver problems. Your doctor will do blood tests before and during treatment. See additional Important Safety Information, including BOXED WARNING, below.

VEOZAH is proven to reduce the number and severity of hot flashes, day and night, based on clinical studies measuring efficacy at 4 and 12 weeks. While everyone’s experience differs, some women had fewer and less severe hot flashes and night sweats within a few weeks after starting VEOZAH. Dr. Ashton emphasizes the importance of speaking with your healthcare provider about what this may mean for you.

It is important to have an open conversation with your doctor about what you’re experiencing, so you can choose the best treatment plan for you going forward. 

What is VEOZAH (fezolinetant)?

VEOZAH is a prescription medicine used to reduce moderate to severe vasomotor symptoms due to menopause. VEOZAH is not a hormone. Vasomotor symptoms are the feelings of warmth in the face, neck, and chest, or sudden intense feelings of heat and sweating (“hot flashes” or “hot flushes”). 

IMPORTANT SAFETY INFORMATION

VEOZAH can cause serious side effects, including

• Liver Problems. Your healthcare provider will do a blood test to check your liver before you start taking VEOZAH. Your healthcare provider will also do this blood test monthly for the first 3 months, at month 6, and month 9 after you start taking VEOZAH or if you have signs or symptoms that suggest liver problems. If your liver blood test values are elevated, your healthcare provider may advise you to stop treatment or request additional liver blood tests.

Stop VEOZAH right away and call your healthcare provider if you have the following signs or symptoms of liver problems:

• feeling more tired than you do usually
• decreased appetite
• nausea
• vomiting
• itching
• yellowing of the eyes or skin (jaundice)
• pale feces
• dark urine
• pain in the stomach (abdomen)

Do not use VEOZAH if you:

• have cirrhosis.
• have severe kidney problems or kidney failure.
• are taking certain medicines called CYP1A2 inhibitors. Ask your healthcare provider if you are not sure.

Before you use VEOZAH, tell your healthcare provider about all of your medical conditions, including if you:

• have liver disease or problems.
• have kidney problems.
• have any medical conditions that may become worse while you are using VEOZAH.

Tell your healthcare provider about all the medicines you take, including prescription and over-the-counter medicines, vitamins, and herbal supplements. VEOZAH may affect the way other medicines work, and other medicines may affect how VEOZAH works.

The most common side effects of VEOZAH include:

• stomach (abdominal) pain 
• diarrhea
• difficulty sleeping (insomnia) 
• back pain
• hot flashes or hot flushes 

These are not all the possible side effects of VEOZAH. Tell your healthcare provider if you have any side effect that bothers you or does not go away.

Call your healthcare provider for medical advice about side effects. You are encouraged to report negative side effects of prescription drugs to the FDA. Visit www.fda.gov/medwatch or call 1-800-FDA-1088. 

Please see full Prescribing Information and Patient Information, including BOXED WARNING.

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