Numbness in one hand is a sign of a nerve problem. The problem may stem from the peripheral nerve (the end nearer the hand) or further proximally, in the spine or even the brain.
The first thing to do is to seek medical attention from a general practitioner, who will take the relevant medical history and perform basic clinic examinations to exclude severe conditions such as stroke.
He or she will then refer the individual to a hand and wrist specialist should a peripheral nerve problem be suspected, a spine surgeon should a spinal nerve root problem be suspected, or a neurologist should a brain problem be suspected.
