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.

"The body is at attention in a way," says orthopaedist Dr Caroline Werkmeister in describing the phenomenon, meaning that nerves are transmitting impulses they normally would ignore. As a result, there are brief, spontaneous contractions of so-called muscle fascicles, which are bundles of skeletal muscle fibres.

Usually this is nothing to worry about, Werkmeister says. In rare cases, however, the twitching is a side effect of medication or has a more serious cause, such as an electrolyte imbalance or a nerve disorder.

Is there anything you can do to prevent the twitching? Yes – try taking it down a notch. There's a reason the nerves are irritated: typically too little rest, too much stress or an exceptional emotional state.

So it's a good idea to find a way to relax. Werkmeister recommends autogenic training "or an age-old trick: Simply get a good night's sleep." – dpa