What is a hot flash, and how does it feel?

A hot flash (in the UK, a hot flush) is an intense feeling of heat that suddenly rises through the upper body. It often starts in the face, neck and chest. Your skin may redden and you may break out in a sweat. As the flash passes, you may feel cold and shivery instead. Some people feel restless or anxious at the same time, or notice their heart speeding up (The Menopause Society, Hot Flashes).

A flash usually lasts between 1 and 5 minutes. How strong it is varies a lot from person to person. In a mild flash you only feel a warm wave and do not sweat. A severe flash can make you stop what you are doing (The Menopause Society, Hot Flashes).

Hot flashes that come during sleep are called night sweats. You wake up sweating, sometimes with damp sheets. We explain how night sweats affect sleep on a separate page: Night sweats.

In medicine, hot flashes and night sweats together are called “vasomotor symptoms.” Vasomotor means related to blood vessels widening and narrowing.

Why do hot flashes happen?

During the transition to menopause, the hormone estrogen made by the ovaries declines and fluctuates. According to The Menopause Society, this drop affects the area of the brain that regulates body temperature. As a result, the body reads even very small changes in temperature as overheating. To release heat, the blood vessels in the skin widen. The sudden heat, flushing and sweating come from this (The Menopause Society, MenoNote: Night Sweats).

How common are hot flashes?

Hot flashes and night sweats are the most commonly reported symptoms of the menopause transition. The Menopause Society states that up to 80 percent of women have these symptoms (The Menopause Society, Hot Flashes). The NHS also puts hot flushes and night sweats at the top of its list of menopause and perimenopause symptoms (NHS, Symptoms).

In Türkiye, the Ministry of Health’s Public Health Directorate (HSGM) also lists hot flashes and sweating among the main symptoms of the menopause period (HSGM).

Hot flashes can start while you still have periods, that is, in perimenopause. If you are wondering what perimenopause is, see this page: What is perimenopause?

How many years do hot flashes last?

There is no single answer to this question. Sources give different ranges:

  • The NHS says menopause symptoms usually last 7–9 years and sometimes continue longer (NHS, Symptoms).
  • The Menopause Society states that hot flashes and night sweats last 7–10 years on average (The Menopause Society, Hot Flashes).
  • The Turkish Ministry of Health writes that symptoms usually last 1–2 years and can sometimes stretch to 5–10 years (HSGM).

Detailed data come from the SWAN study in the US. This study followed 3,302 women for years. Among the 1,449 women with frequent hot flashes, the total duration of symptoms was a median of 7.4 years. Here “frequent” means having flashes on at least six of the last 14 days. In women whose last period could be observed, flashes continued for a median of 4.5 more years after the last period (Avis et al., 2015).

In the same study, the timing of onset mattered. In women whose flashes began while their periods were still regular or early in perimenopause, the total duration was a median of more than 11.8 years. In those whose flashes began after menopause, they lasted a median of 3.4 years. Younger age, higher perceived stress, sensitivity to symptoms, and symptoms of low mood and anxiety were also linked with a longer duration (Avis et al., 2015).

These figures are averages. Yours may be shorter or longer. The Menopause Society notes that for most people symptoms ease over time and go away within a few years (The Menopause Society, MenoNote: Night Sweats).

What triggers hot flashes, and who gets them more often?

The Menopause Society lists some risk factors. Ethnic background is one of them. More fat around the belly increases the chance of hot flashes, especially in younger women and early in the transition (The Menopause Society, Hot Flashes).

Some things can trigger individual flashes. Both The Menopause Society and the NHS list alcohol, caffeine, spicy food and hot drinks as possible triggers (The Menopause Society, Hot Flashes; NHS, Things you can do). Not everyone has the same triggers. The easiest way to find yours is to write down your flashes next to what you ate and drank that day for a few weeks.

What else can hot flashes be a sign of?

Not every wave of heat is menopause. The Menopause Society stresses that hot flashes and night sweats have many causes besides menopause. An overactive thyroid gland, diabetes, sleep apnea, stomach acid coming back up into the food pipe (reflux), anxiety and low mood are some of them. More serious causes, such as some infections and blood cancers, can also lead to night sweats (The Menopause Society, MenoNote: Night Sweats).

Medications are another important area. Some antidepressants, painkillers, steroids and heart medications can increase sweating. If flashes appeared after you started a new medication, ask your clinician about it (The Menopause Society, MenoNote: Night Sweats).

If the flashes started while your periods were still regular, stopped for a while and came back, or appeared years after you stopped hormone therapy, menopause is not the likely cause. In that case an assessment is needed (The Menopause Society, MenoNote: Night Sweats).

What can you observe yourself?

A few pieces of information are very useful when you see your clinician:

  • When did the flashes first start?
  • How many times a day or night do they come?
  • How strong are they? Do they make you stop what you are doing?
  • Do they wake you at night?
  • Do they come with a particular food, drink or situation?
  • What are your periods like? When was your last period?
  • Do you have fever, weight loss or swelling in your neck or armpits?

The answers to these questions are hard to keep in your head. Taking short notes for a few weeks brings out the pattern.

What can make a difference in daily life?

The NHS makes some general suggestions. They include wearing thin, light clothing, keeping the bedroom cool at night, finding ways to reduce stress, moving regularly and staying at a healthy weight. The NHS also notes that cognitive behavioral therapy (a talking therapy that focuses on patterns of thinking and behavior) can help with hot flashes (NHS, Things you can do).

The Menopause Society also lists weight loss and cognitive behavioral therapy among low-risk options. It notes that the evidence for methods such as cooling the room or your clothing is limited (The Menopause Society, Hot Flashes). These suggestions do not always make the flashes go away, but they can make daily life easier.

The NHS advises talking to a doctor before using herbal or complementary products (NHS, Things you can do). The Turkish Ministry of Health also advises against taking any medication for menopause complaints without consulting a doctor (HSGM). This page does not cover treatment options; talk through your options with your clinician.

When should you see a doctor about hot flashes, and what should you ask?

The NHS suggests seeing your GP if you have menopause symptoms and want to learn about your options (NHS, Symptoms). If the flashes are affecting your sleep, your work or your relationships, you do not need to wait. A blood test is often not needed either: according to the NICE guideline, at 45 and over, if new hot flashes come together with a change in the menstrual cycle, a clinician can identify perimenopause from the symptoms, without a lab test (NICE NG23, 1.3.1).

At the appointment you could ask:

  • Are these flashes consistent with the menopause transition, or should another cause be considered?
  • Could one of the medications I take be increasing my sweating?
  • What options are there for my situation, and what are their pros and cons?