Myoclonus (my-o-klo-nus) is a sudden, involuntary twitching, jerking,
or contraction of a muscle
or group of muscles.
More to Know
Muscles are controlled by electrical impulses in the central nervous
system. Sometimes, even healthy people experience an abnormal electrical impulse
that can cause a muscle or group of muscles to contract suddenly. Hiccups are an example
of this type of contraction, and so are the muscle twitches that many people experience
as they try to fall asleep.
Brief myoclonus in a single muscle can be a normal, harmless occurrence, but in
some cases involuntary muscle twitching can be a symptom of a serious condition like
epilepsy, stroke, brain
tumors, infection, multiple sclerosis, genetic disorders, metabolic disorders, or
an injury to the brain or spinal cord.
Keep in Mind
In healthy people, brief, occasional muscle twitches are generally nothing to worry
about. If myoclonus happens a lot, lasts long, or is associated with other symptoms,
it should be evaluated by a doctor to determine if an underlying condition is the
cause. Treatment for myoclonus usually involves treating the muscle contractions and
their underlying cause with medications.
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