Uncontrolled movements of the body. These movements occur spontaneously and may be slow and writhing (see athetosis); rapid, jerky, and random (see chorea); or predictable, stereotyped, and affecting 1 part of the body, usually the face (see tic). They may be a feature of a disease (for example, Huntington’s disease) or a side effect of certain drugs used to treat psychiatric conditions.
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