Hot Flashes

1 What are Hot Flashes?

Hot flashes (also known as hot flushes) are a form of flushing due to reduced levels of estradiol. Hot flashes are a symptom which may have several other causes, but which is often caused by the changing hormone levels that are characteristic of menopause.

They are typically experienced as a feeling of intense heat with sweating and rapid heartbeat, and may typically last from two to thirty minutes for each occurrence.

2 Symptoms

Intense feeling of heat that usually begins in the face or chest is the main symptom of hot flashes. Although it may appear elsewhere such as the back of the neck, and spreads throughout the whole body.

Some women feel as if they are going to faint. In addition to being an internal sensation, the surface of the skin, especially on the face, becomes hot to the touch. This is the origin of the alternative term "hot flush", since the sensation of heat is often accompanied by visible reddening of the face. Excessive flushing can lead to rosacea.

This event may be repeated a few times each week or every few minutes throughout the day. Hot flashes may begin to appear several years before menopause starts and last for years afterwards. Some women undergoing menopause never have hot flashes. Others have mild or infrequent flashes.

The worst sufferers experience dozens of hot flashes each day. In addition, hot flashes are often more frequent and more intense during hot weather or in an overheated room, the surrounding heat apparently making the hot flashes themselves both more likely to occur, and more severe.

Severe hot flashes can make it difficult to get a full night's sleep (often characterized as insomnia), which in turn can affect mood, impair concentration, and cause other physical problems. When hot flashes occur at night, they are called "night sweats". As estrogen is typically lowest at night, some women get night sweats without having any hot flashes during the daytime.

Young women
If hot flashes occur at other times in a young woman's menstrual cycle, then it might be a symptom of a problem with her pituitary gland; seeing a doctor is highly recommended. In younger women who are surgically menopausal, hot flashes are generally more intense than in older women, and they may last until natural age at menopause.

Hot flashes in men could have various causes. It can be a sign of low testosterone. Another is andropause, or "male menopause".

Men with prostate cancer or testicular cancer can also have hot flashes, especially those who are undergoing hormone therapy with antiandrogens, also known as androgen antagonists, which reduce testosterone to castrate levels.

There are also other ailments and even dietary changes which can cause it. Men who are castrated can also get hot flashes.

Some menopausal women may experience both standard hot flashes and a second type sometimes referred to as "slow hot flashes" or "ember flashes".

The standard hot flash comes on rapidly, sometimes reaching maximum intensity in as little as a minute. It lasts at full intensity for only a few minutes before gradually fading.

Slow "ember" flashes appear almost as quickly but are less intense and last for around half an hour. Women who experience them may undergo them year round, rather than primarily in the summer, and ember flashes may linger for years after the more intense hot flashes have passed.

3 Causes

Menopause is the commonest cause of hot flashes.

Apart from that, other factors that are implicated include:

  • Food and drink - Spicy foods can bring on hot flashes and sweating, but they’re not the only culprits. Caffeine and alcohol can also be triggers. For some people, even just eating a large meal can cause flushing similar to menopausal hot flashes. These causes are pretty obvious though, as symptoms develop soon after consuming the food or beverage at fault.
  • Medications - Hot flashes are also associated with a number of prescription drugs. Lupron, which is sometimes used for treatment of uterine fibroids, can cause menopause symptoms, as can anti-hypertensives, antidepressants, and anti-anxiety medication.

Usually, the hot flashes start after beginning a new medication and stop once the medication is discontinued. That helps differentiate one that is induced by medication from one that is due to menopause.

  • Pancreatic tumors and other hormone-secreting tumors - Cells in the pancreas create and release hormones to keep the body functioning properly, but this process can go awry if there are certain kinds of pancreatic tumors also releasing hormones.

One result may be hot flashes and/or sweating. Malignant and non-malignant tumors in other organs can secrete hormones too, but these tumors are relatively rare and an uncommon cause of hot flashes.

  • Hyperthyroidism - Your thyroid (an endocrine gland that controls metabolism by creating hormones that the body then uses to convert food to energy) regulates almost all organs and tells them the speed at which to work.

Hyperthyroidism occurs when there is an overabundance of thyroid hormones. This causes the body’s metabolism to increase, which can result in heavier-than-usual sweating and difficulty handling heat. The symptoms may sound similar, but they feel different from “true” hot flashes.

  • Thyroid cancer - Thyroid cancer can also cause an excess of thyroid hormones, leading to sweating and excessive warmth, but hyperthyroidism is a much more likely cause.
  • Rush of adrenaline - An adrenaline surge through the body can cause a feeling of warmth that can feel similar to a hot flash. Any sudden excitement or stress can cause an adrenaline rush.

The presence of a trigger — such as a stressful event immediately before — helps to differentiate an adrenaline-induced hot flash from a menopause-related hot flash.

  • Other cancers - Certain cancers, particularly lymphomas and leukemias, may cause night sweats and fevers that feel like hot flashes. But these usually come with other symptoms such as weight loss, decreased appetite or pain.
  • Other culprits - Additional, though less likely, reasons for hot flashes and night sweats include HIV infection and tuberculosis.

4 Making a Diagnosis

Hot flashes are usually self-diagnosed, but it is important for your doctor to know that they are happening to you.

After noting your age, your doctor will ask you whether you are still having regular menstrual periods.

If you are not, your doctor will ask the approximate date of your last period. If you are still menstruating, the doctor will want to know whether there is anything unusual about the timing of your periods or the amount of blood flow.

Your doctor will ask whether you are experiencing any other symptoms that may be related to decreased estrogen, such as vaginal dryness, pain or discomfort during intercourse or urinary incontinence.

Finally, your doctor will review your medical history, your gynecological history and the types of medications you are taking. This is to make sure your symptoms are hot flashes and not the result of a medical or gynecological illness or a side effect of medication.

In most cases, your doctor can confirm that your hot flashes are related to menopause by reviewing your menstrual history and conducting a physical exam, including a pelvic exam.

Your doctor may order a blood test to measure serum levels of follicle stimulating hormone (FSH), which are high during menopause.

5 Treatment

Several treatment methods exist for hot flashes.

  • Nonprescription remedies: Although many non-prescription remedies reduce hot flashes, it’s likely that this is because of the “placebo effect.” Let your healthcare provider know if you are taking a nonprescription remedy.

    Nonprescription remedies you may consider for hot flash relief include:

    • Soy: Eat one or two servings of soy foods daily (containing isoflavones), such as low-fat varieties of tofu, tempeh, soy milk, or roasted soy nuts. Supplements containing soy isoflavones, such as Promensil, reduce hot flashes in some studies.
    • Herbs: Supplements containing certain herbs like black cohosh, such as Remifemin, decrease hot flashes in some studies.
  • Prescription therapies: The following prescription medications reduce hot flashes more than placebos in scientific studies. They may be good options if you have frequent, bothersome hot flashes. 

    Every medication has risks and side effects. Review your medical history with your healthcare provider when considering a prescription medication.

  • Hormonal options: 
    • Prescription hormone therapy with estrogen is the most effective treatment for hot flashes. Although using hormones can increase your risk of breast cancer and cardiovascular disease, studies show that benefits may outweigh risks for healthy women younger than age 60 with moderate to severe hot flashes.

      The goal is to use the lowest dose of hormone therapy that treats your symptoms for the shortest time necessary. Women with a uterus need to combine estrogen with a progestogen. 

    • A new option for women with a uterus combines estrogen with bazedoxifene to protect the uterus (Duavee). Bazedoxifene is an estrogen agonist/antagonist, which means it works like estrogen in some tissues and opposes estrogen’s actions in others.
    • If it has not been a full year since your last period and you are a healthy nonsmoker, you may consider a combination estrogen-progestin birth control pill. This will provide contraception, hot flash relief, and regular periods.
  • Non-hormonal options: You also may consider the following non-hormonal medications. They are more effective than placebo in scientific studies, although not as effective as hormone therapy.
    • Low-dose paroxetine (Brisdelle) is the only government-approved non-hormonal option for treating hot flashes.
    • Certain drugs approved to treat depression reduce hot flashes in women without depression. Effective drugs include paroxetine (Paxil), venlafaxine (Effexor), and escitalopram (Lexapro). You should not take paroxetine if you take tamoxifen for breast cancer.
    • Gabapentin (Neurontin) is a drug approved to treat epilepsy, migraine, and nerve pain, but it also reduces hot flashes. It can cause excessive sleepiness, so it is an especially good option if you have bothersome night sweats and take your gabapentin at bedtime.
    • Sleeping medications such as Ambien, Lunesta, and Benadryl will not reduce your hot flashes but may help you sleep through them.

6 Prevention

Hot flashes related to menopause cannot be prevented.

However, the following lifestyle changes may help to make hot flashes less severe or less frequent:

  • Drink a glass of cool water at the beginning of a hot flash. This seems to lessen discomfort in some women. Also, be sure to drink enough water, usually six to eight glasses per day.
  • Avoid drinking beverages that contain caffeine or alcohol, since these can make hot flashes more uncomfortable.
  • Cut down on red wine, chocolate, and aged cheeses. They contain a chemical that can trigger hot flashes by affecting the brain's temperature control center.
  • Don't smoke. Smoking can make hot flashes worse.
  • Wear loose, comfortable clothing made of cotton to help absorb perspiration.
  • Dress in layers, so that you can remove some clothing if you suddenly feel hot.
  • Lower your home thermostat to keep your house cool. At work, open a window or use a small portable fan.
  • At night, use lightweight blankets that can be removed if hot flashes wake you up.
  • Regular vigorous exercise during which endorphins are produced may also decrease hot flashes.

7 Alternative and Homeopathic Remedies

A few alternative remedies exist for hot flashes.

Herbal remedies for women with hot flashes include:

  1. Plants that cool the system, such as chickweed, elder and violet;
  2. Plants that nourish or increase oxygen utilization in the liver, such as dong quai, dandelion, Ho Shou Wu (polygonum multiflorum) and yellow dock; and
  3. Plants rich in phytosterols, such as black cohosh.

8 Lifestyle and Coping

Staying cool and reducing stress are the principal lifestyle changes to treat your hot flashes.

Researchers find that women with hot flashes have more sensitive thermostats in their brain, so are comfortable only in a small range of temperatures.

Some women can find relief with these options:

  • Avoid warm rooms, hot drinks, hot foods, alcohol, caffeine, excess stress, and cigarette smoking.
  • Wear layers of clothing made from light, breathable fabrics, removing a layer or two when you’re hot and replacing them when you’re cooler.
  • Cooling products, including sprays, gels, and the Chillow pillow may be helpful.
  • To reduce stress and promote more restful sleep, exercise regularly, but not too close to bedtime. Meditation, yoga, qigong, tai chi, biofeedback, acupuncture, or massage also will lower your stress levels.
  • When a hot flash is starting, try “paced respiration”—slow, deep, abdominal breathing, in through your nose and out through your mouth. Breathe only 5 to 7 times per minute, much more slowly than usual.
  • Try different strategies to stay cool while sleeping. Dress in light, breathable nightclothes. Use layered bedding that can be easily removed during the night. Cool down with a bedside fan.

    Keep a frozen cold pack or bag of frozen peas under your pillow, and turn the pillow often so that your head is always resting on a cool surface. If you wake at night, sip cool water.

    Try different techniques for getting back to sleep, such as meditation, paced respiration, or getting out of bed and reading until you become sleepy.

  • Women who are overweight have more hot flashes, so maintain a healthy weight and exercise regularly to decrease bothersome hot flashes and improve your overall health.

9 Risks and Complications

There are several risks and complications associated with hot flashes.

Hot flashes are associated with increased awake and sleep systolic BP independent of menopausal status.

Nighttime hot flashes (night sweats) can wake you from sleep and, over time, may cause chronic insomnia. These sleep disturbances can, in turn, eventually lead to memory problems, anxiety and depression in some women.

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