Why Does My Arm Fall Asleep?

Is that your spidey-sense tingling? Nope, it's a cry of suffocation. Your arm can't reach for anything when blood can't reach your arm.  If you leave a limb in a position that constricts or otherwise impairs blood circulation, the limb's malnourished nerves will start to malfunction. You may experience tingling, pain or numbness in the blood-deprived area as your sensory neurons fail. The tingling "pins and needles" sensation, known as paresthesia, can also result from sustained pressure on a nerve, or in rare cases, from neurological disorders (like strokes).

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