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Muscle twitching
Definition
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.
Common 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:
- Amyotrophic lateral sclerosis (ALS - Lou Gehrig's disease)
- Damage to the nerve that leads to a muscle
- Muscular dystrophy
- Spinal muscular atrophy
- Weak muscles (myopathy)
Symptoms that suggest a nervous system disorder include:
- Loss of, or change in sensation
- Loss of muscle size (wasting)
- Weakness
Home Care
There is usually no treatment necessary for benign muscle twitching.
Call your health care provider if
Call your health care provider if you have long-term or persistent muscle twitches.
What to expect at your health care provider's office
Your health care provider will take a medical history and perform a physical examination.
Medical history questions 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 in the same location?
- Are you pregnant?
- What other symptoms do you have?
Diagnostic tests vary depending on the suspected cause. Tests may include:
- Blood tests to look for problems with electrolytes, thyroid gland function, and blood chemistry
- Electromyogram
- Nerve conduction studies
- MRI of the spine, and sometimes of the brain
References
Barohn RJ. Muscle diseases. In: Goldman L, Ausiello D, eds. Cecil Medicine. 23rd ed. Philadelphia, Pa: Saunders Elsevier; 2007: chap 447.
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.




















