Tardive Dyskinesia - Definition

In general, tardive dyskinesia (TD) refers to a wide variety of involuntary, repetitive, persistent, stereotypic movements caused by the use of drugs that block dopamine receptors. These drugs that block dopamine receptors are known as dopamine-receptor antagonists or DRAs. Involuntary movements such as those associated with dystonia, myoclonus, tics, and tremor, and restlessness with muscle quivering and the urge to move (akathisia) may be manifestations of TD. When used in the classic sense, TD refers to an iatrogenic disorder produced by the long-term use of drugs to treat schizophrenia that act by blocking dopamine receptors.

Dyskinesia is from the Greek words, dys and kinEsis, meaning difficulty of movement. Tardive comes from the French word (tardif) for tardy or late, meaning that the dyskinesias appear late in the course of therapy with a drug that blocks dopamine receptors (DRAs). These movements do not occur as an immediate response to the use of the drug.

	Symptoms