That sudden wave of heat is one of the most recognisable signs of the menopause transition — here's what's actually happening and how to manage it.
A hot flash (or hot flush) is a sudden feeling of intense warmth, usually most noticeable in the face, neck, and chest. It's often accompanied by sweating, a rapid heartbeat, and a flushing of the skin. When they happen at night, they're called night sweats. Hot flashes are the most common symptom of perimenopause and menopause, affecting up to 80% of women.
Hot flashes are triggered by declining estrogen levels. Estrogen plays a role in regulating the hypothalamus — the brain's thermostat. As estrogen falls during perimenopause, the hypothalamus becomes hypersensitive. It misreads the body's normal temperature as too hot and triggers a cooling response: blood vessels in the skin dilate (causing flushing and redness) and sweat glands activate.
This results in the sudden heat wave sensation, followed by sweating and often a chill as the body overcools. The whole episode typically lasts 1–5 minutes but can feel much longer.
While declining estrogen is the underlying cause, certain things can trigger or worsen individual episodes:
HRT replaces the estrogen (and sometimes progesterone) that declines during menopause. It reduces hot flash frequency and severity by up to 90% in most women and is the most effective treatment available. Modern HRT (especially body-identical HRT) is considered safe for most women and should be discussed with a doctor.
Certain antidepressants — particularly venlafaxine (Effexor), paroxetine, and escitalopram — significantly reduce hot flash frequency even in women who aren't depressed. These are a good option for women who can't or prefer not to take HRT, including breast cancer survivors.
A newer non-hormonal prescription medication that specifically targets the NK3 receptor in the brain involved in hot flashes. It reduces hot flash frequency by around 60% and is approved for moderate-to-severe menopausal hot flashes in many countries.
Keeping rooms cool, wearing breathable cotton layers, carrying a fan, avoiding known triggers, and maintaining a healthy weight can all reduce hot flash frequency and severity. These aren't as effective as medication but have no side effects.
CBT helps women manage how they react to hot flashes and reduces the distress they cause. It may also reduce frequency in some women. The NHS offers CBT specifically for hot flashes.
Soy isoflavones, red clover, and black cohosh are popular supplements for hot flashes, but the evidence for their effectiveness is mixed and modest at best. If you try supplements, let your doctor know — some (like black cohosh) have rare interactions with medications.
Log hot flash frequency, severity, and potential triggers with WomensPal. Seeing patterns can help you avoid triggers and track whether treatment is working.
Start tracking free →Declining estrogen affects the hypothalamus, making it hypersensitive to normal body temperature. It triggers a cooling response — blood vessel dilation and sweating — even when the body isn't actually overheating. The result is a sudden wave of heat and sweating.
An individual episode lasts 1–5 minutes. The overall hot flash phase averages about 7 years, though some women experience them for much shorter or longer periods.
HRT is the most effective treatment, reducing frequency and severity by up to 90%. Non-hormonal options include SSRIs/SNRIs and the newer fezolinetant. Lifestyle changes can also help reduce severity.
Common triggers include hot drinks, caffeine, alcohol (especially red wine), spicy food, smoking, stress, warm rooms, and tight clothing. Triggers vary between women — keeping a diary helps identify personal triggers.
Related: Perimenopause Symptoms · Menopause Symptoms · Hormone Imbalance Symptoms · Estrogen Dominance