Alternate Names: Muscle fasciculation; Muscle twitching

Considerations: Muscle twitching is the result of minor local muscle contractions or the uncontrollable twitching of a single muscle group served by a single motor nerve fiber or filament.

Muscle twitches are minor and often go unnoticed. Some are common and normal, while others indicate a neurologic disorder.

Common Causes:

• Benign, nonpathologic fasciculations (not caused by disease or disorders)
  • Often affect the eyelids, calf, or thumb
  • Normal and quite common, often triggered by stress or anxiety
• A diet deficiency
• Drug overdose
• Drug side effect (such as diuretics, corticosteroids and estrogens)
• Exercise

Symptoms suggestive of a neurological cause of fasciculations include:

• Atrophy of muscle
• Weakness
• Other findings of nerve dysfunction

Neurological illnesses where fasciculations are seen include:

• Chronic denervation of muscle due to disc compression of nerve exiting the spinal cord
• ALS (Lou Gehrig's Disease)
• Spinal muscular atrophy
• Muscular dystrophy
• Myopathy

Home Care: There is usually no treatment necessary.

Call If:

Call your health care provider if there are prolonged or persistent muscle twitches.

What To Expect: The medical history will be obtained and a physical examination performed.

Medical history questions documenting your fasciculations in detail may include:

• When did you first notice the twitching?
• How long does it last?
• How often do you experience twitching?
• What muscles are affected?
• Is it always the same location
• Are you pregnant?
• What other symptoms are also present?