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"Why do my arms fall asleep at night?"

ZocdocAnswersWhy do my arms fall asleep at night?


I've been waking up lately with one arm or the other completely, totally numb. It's scary - I have to move the numb arm around with the othe rone and slap it to bring the feeling back. Is this some kind of nerve disfunction? I'm a guy age 22.


This sounds like a distressing problem. As you know it is not uncommon for a limb to "fall asleep" from time to time. It occurs when blood flow is temporarily stopped from getting into an arm or leg. Feeling is lost in that limb until blood flow (and oxygen) returns. It often happens when you spend more than a few minutes with your legs crossed, or while lying in an awkward position while sleeping. Most likely, this is all you are experiencing. However, there are other possible causes for this problem. Sometimes, atherosclerosis, a disease of the arteries, can cause an obstruction of blood flow to a limb. This is a very unusual in men your age. Another possibility is that you have something called thoracic outlet syndrome. This is when the clavicle, ribs, and shoulder bones are too close together and cause an obstruction to blood vessels and nerves that go to one of you arms. Most often the symptoms are pain and tingling in the hand and arm. Numbness, while often present, usually does not occur without the pain. Thoracic outlet syndrome is something that can be diagnosed in the office. The best type of physician for you to see about this problem is a primary care physician such as a family doctor or internal medicine doctor. Good luck.

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