Are Night Sweats a Symptom of Cancer?

woman sweating in bed
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If you've been experiencing night sweats, you may be wondering whether they are a symptom of cancer. 

First, you should know that night sweats are common. Just about everyone will experience them at some point. Second, you should consider whether what you are experiencing are true night sweats. Night sweating is defined as sweating so profusely that your bed clothes—and possibly even your linens—need to be changed.

Learn more about how the symptom is defined and what it means for your health, below.

Night Sweats vs. Hot Flashes vs. Flushing

Some people confuse night sweats with hot flashes or flushing, which are similar to night sweats but are not the same. Hot flashes are sudden, strong, warm sensations that may begin in the chest and move upward to the face. They can occur any time of the day, not just at night. Flushing is the sudden rise in body temperature that can cause a rosy or reddening appearance to the skin.

Are Night Sweats a Cancer Symptom?

Night sweats can be a symptom of many types of cancer and they're most often associated with lymphoma. However, unless they are accompanied by other symptoms that are typical of lymphoma, your doctor may not immediately suspect the disease in his or her evaluation.

It's important to note that night sweats are not a symptom that's exclusive to cancer. Though night sweats are a key lymphoma symptom, many other conditions are more likely to cause them than cancer. In fact, the number one cause of night sweats is menopause (or medications that induce menopause).

Getting an Accurate Diagnosis

Your doctor will likely give you a physical exam that includes routine blood work to determine the cause of night sweating. He or she will want to know how often you have night sweats and when they began. Your personal health history and your medications will also be taken into consideration by your doctor. It is very important that your doctor is aware of any medications that you are taking, whether they are prescribed, over-the-counter, or herbal supplements.

If It's Not Cancer, What Causes Night Sweats?

You should first evaluate your sleeping environment. Are you sleeping in heavy pajamas? Do you have too many blankets on your bed? Is your thermostat set at a high temperature?

To reduce or eliminate night sweats, try sleeping in lighter clothing or with fewer blankets to see if that alleviates the night sweats. And try setting your room temperature between 60 and 67 degrees—though that might seem chilly, it's actually considered the ideal temperature range for sleep, according to the National Sleep Foundation.

However, be sure that your doctor is aware that you are experiencing night sweats. Don't wait too long for symptoms to improve or go away on their own, especially if they are persistent.

Your medications may cause night sweats, as well. Prescribed medications, such as anti-depressants, are often the culprit of night sweats. Other drugs, like over-the-counter acetaminophen (Tylenol), may also cause night sweats or flushing, so be sure to talk to your doctor or pharmacist about the potential side effects of your medication.

Other conditions that are related to night sweats:

Keep in mind that sometimes there is no medical reason why night sweats may occur.