Should you worry when your muscles twitch involuntarily?

Involuntary muscle twitches are called fasciculations, and though annoying, they are usually harmless.

They can occur in your hand, eyelid, and sometimes in your leg or elsewhere. Involuntary muscle twitches that are visible under the skin are called fasciculations, and they can be quite annoying. But are they something to worry about?

Probably not, doctors say. Muscle twitching is extremely common and typically caused by irritability of the nerve fibres.