You're relaxing on the sofa when suddenly your eyelid starts twitching. Or perhaps it's a muscle in your arm, your leg, or your foot that begins to spasm—sometimes for a few seconds, sometimes for ...

Muscle twitching is often caused by stress, lack of sleep, or too much caffeine. If muscle twitching happens with muscle weakness or wasting, you should see a doctor. Muscle twitches can be due to ...