Muscle twitches are fine movements of a small area of muscle.
Alternative Names
Muscle fasciculation; Fasciculations of muscle
Considerations
Muscle twitching is caused by minor muscle contractions in the area, or the uncontrollable twitching of a muscle group that is served by a single motor nerve fiber or filament.
Muscle twitches are minor and often go unnoticed. Some are common and normal. Others are signs of a nervous system disorder.
Causes
Diet deficiency
Drug overdose (caffeine)
Drug side effect (such as from diuretics, corticosteroids, or estrogens)
Exercise
Twitches not caused by disease or disorders (benign twitches)
Often affecting the eyelids, calf, or thumb
Normal and quite common, often triggered by stress or anxiety
Come and go, and do not last for more than a few days
Nervous system conditions that can cause muscle twitching:
Review Date:
11/13/2008
Reviewed By:
David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine; and Daniel B. Hoch, PhD, MD, Assistant Professor of Neurology, Harvard Medical School, Department of Neurology, Massachusetts General Hospital. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.