Hot flashes are sudden feelings of warmth. A hot flash is a feeling that you have intense warmth which is not caused by an external source. They are usually most intense over the chest, neck and face. The skin can redden, as if people are blushing. Hot flashes can also cause sweating and if you lose too much body heat, then you can feel chilled afterward. There are some medical conditions which can lead to hot flashes but they are most common caused by menopause (this is the time when menstrual periods become irregular and eventually stop). 
The most common symptoms of menopausal transition are hot flashes .How often they can happen, varies among women and they can range from a few a week to several an hour. There are many different treatments that can be used for hot flashes. Hot flashes can appear suddenly but also there are some women who can feel them coming on over a period of a few minutes. Many women also get chills or feel cold as the hot flash lets up. Hot flash spread over the body and they last from thirty seconds to a few minutes.
They can be accompanied by redness of the skin which is also known as flushing but also there can be excessive sweating. It is said that about 70% of women will experience hot flashes at some point in their menopausal transition. 
Hot flashes symptoms
During a hot flash, you might have:
- A chilled feeling as the hot flash lets up
- Perspiration, mostly on your upper body
- Sweating, especially in the upper body
- Rapid heartbeat. This means that you are experiencing a heartbeat which is faster than usual.
- A flushed appearance with red, blotchy skin
- A sudden feeling of warmth spread through your upper body and face
- Tingling in your fingers
- Having skin that suddenly feels warm
It can vary in intensity and frequency. How long symptoms will last, it varies greatly. On average, symptoms of hot flashes persist more than 7 years . There are some women who will have them for more than ten years. If your hot flashes become bothersome, then you should see your doctor to talk with him about the best treatment for you. Every single person can experience a hot flash. How long will they last, depend on what triggers them. Hot flash in young women, men or during pregnancy can be due to medical conditions which interfere their body ability to regulate temperature.
Hot flashes causes
The cause for hot flash is not known but it is related to several factors. These causes include changes in your body’s thermostat (hypothalamus) and reproductive hormones, which can become more sensitive to slight changes in the body temperature. Also some people think that hormonal changes in your body are thought to cause hot flash. This reaction can be triggered by several factors and these, potential triggers, are:
- Some medications, including raloxifene (Evista), tamoxifen and tramadol 
- Spinal lesions
- Chemotherapy 
- Pregnancy, particularly during the first and second trimesters 
- Stress and anxiety
- Wearing tight clothing
- Being in a warm room
- Caffeine 
- Hot drinks
- Spicy foods 
But there are many possible causes for hot flashes and the mentioned list is not comprehensive. If you are experiencing repeated hot flashes which do not go away, then you should visit your doctor as soon as possible.
Not all women who are going through menopause will have hot flash. It is not clear why some women to have them. Here are some factors which can increase the risk of having hot flashes:
- Ethnicity: There are many cases in which is shown that African – American women are reporting menopausal hot flashes more than women from Europe. But the hot flash is less common in women of Chinese and Japanese than in white European women. 
- Smoking: Women who smoke are having increased chances of getting hot flashes. 
- Obesity: If you have a high BMI (body mass index), then you have higher chances of getting a hot flash.
Night sweats (nighttime hot flashes) can wake you from sleep and over time it can cause chronic insomnia. There is some association with hot flash and increased risk of bone loss and heart disease. 
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