Muscle twitching is caused by minor muscle contractions in the area or uncontrollable twitching of a muscle group that is served by a single motor nerve fiber. Twitching muscles can happen for lots of reasons, including stress, too much caffeine, a poor diet, exercise, or as a side effect of some medicines. Here are some common causes of muscle twitching:

• Stress: Stress can cause muscle twitching, especially in the eyelid, thumb, or calf muscles.

• Caffeine: Too much caffeine can trigger muscle twitches in various parts of your body.

• Medications: Some medications, such as diuretics, corticosteroids, estrogens, antidepressants, epilepsy and psychosis drugs, can cause muscle twitches.

• Lack of sleep: Lack of sleep can cause muscle twitches.

• Electrolyte imbalances: Electrolyte imbalances, such as low potassium, can cause muscle twitches.

• Autoimmune disorders: Autoimmune disorders, such as Isaac syndrome, can cause muscle twitches.

• Nervous system disorders: Nervous system disorders, such as amyotrophic lateral sclerosis (ALS), can cause muscle twitches.

Most of the time, muscle twitching is nothing to worry about and goes away on its own. However, if you have long-term or persistent muscle twitches or if twitching occurs with weakness or loss of muscle, you should contact your healthcare provider.