PHARMACOLOGICAL OPTIONS FOR THE MANAGEMENT OF DYSKINESIAS

Dyskinesias are abnormal involuntary movements characterised by an exc essive amount of movement. Typically, these movements are choreiform i n nature. They may be caused by systemic, metabolic, endocrinologic, s tructural, vascular, infectious or inherited degenerative conditions, or be toxin- or drug-induced. With many non-drug-induced dyskinesias, treatment of the underlying condition may be sufficient to eliminate t he movements, although temporary treatment may be required to control the movements if they are severe. Drug-induced dyskinesias often resol ve when the offending drug is discontinued. A notable exception is tar dive dyskinesia, which is caused by exposure to dopamine receptor bloc king drugs, the majority of which are antipsychotic agents. Tardive dy skinesias will persist, or may even develop after the causative agent has been stopped and may not spontaneously remit. Another commonly enc ountered form of drug-induced dyskinesia is seen in patients with Park inson's disease who are receiving levodopa. Medications which deplete dopamine are most successful in treating choreiform dyskinesias, altho ugh anticholinergics, GABAergics, serotonergics, and calcium channel b locking: agents have been reportedly beneficial in some cases. Treatme nt of levodopa-induced dyskinesias requires manipulation of the patien t's antiparkinsonian drug regimen.