Dear Straight Dope:
What causes my eyelid to twitch at times? It's annoying and I don't know what to do to stop it.
From DrFidelius, who is not an actual Dr, but who plays around with enough pharmacology to know this stuff:
The most common cause of muscle tics and twitches is stress. Have you been in stressful situations lately? Final exams, new job, are you Monica’s father? Learning relaxation techniques or eliminating the source of your stress could alleviate the symptom.
A tic is a brief, flicking sensation confined to a small part of the body, such as the eyelid; usually indicative of a harmless involuntary muscle contraction. A repetitive, uncontrollable, purposeless contraction of an individual muscle or group of muscles, typically in the face, arms or shoulders; may be a sign that you have a tic related to a minor psychological disorder, a condition related to a brain disorder, or trigeminal neuralgia. Intense, longer-lasting trembling or shaking of a body part or of the entire body; could be symptomatic of caffeine poisoning, alcohol withdrawal, an overactive thyroid gland or Parkinson’s disease. Movements such as shoulder shrugging, mouth twitching and erratic blinking may be signs of a minor psychological disturbance. They most often develop in children ages 7 to 14 as a result of anxiety, and usually stop within a year; some cases may persist into adulthood. The disorder occurs in up to 25 percent of children, and boys exhibit symptoms three times as often as girls. Tics or twitches are sometimes caused by neurological disorders, in which case they are referred to as dyskinesia. This condition may result from brain damage at birth, head trauma or use of the antiemetic (vomit suppressant) drug metoclopramide, or drugs to treat psychiatric ailments. Dyskinesia includes muscle spasms, repetitive fidgets, jerking or writhing movements, or a combination of these symptoms.
CALL YOUR DOCTOR IF:
– Your condition consists of unexpected trembling movements that occur only when the affected body part is at rest; you need to be checked for the possibility of Parkinson’s disease.
– Your tic or twitch is persistent or recurs often; you may be having minor seizures, or you may have a neurological disorder or other condition of a serious nature.
One currently approved treatment for major spasms is the injection of botulinum toxin. This toxin weakens the muscles by blocking nerve impulses transmitted from the nerve endings of the muscles. Kids, don’t try this at home.
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