Tardive dyskinesia and essential fatty acids.

Tardive dyskinesia (TD) is a movement disorder described in individuals who have been treated with anti-dopaminergic agents. The pathophysiology of this condition remains to be fully elucidated. Several mechanisms like dopaminergic supersensitivity, dysfunction of striatonigral, GABAergic neurons and disturbed balance between dopaminergic and cholinergic systems have been described. Essential fatty acids (EFAs) are important components of neuronal membrane and the EFA content of these membranes can significantly influence neuronal functioning. Lower levels of EFAs have been reported in red blood cells (RBC) and plasma of individuals with moderate to severe TD. Supplementation with EFAs (omega-3 and omega-6 and ethyl-EPA) have been tried to alleviate TD in open and double-blind clinical trials and in some animal models of TD. In addition, antioxidants (Vitamin E) and melatonin have been tried. However, smaller numbers of patients and shortened length of clinical studies make it difficult to draw any definitive conclusions. Large multi-centre studies with sound methodology of both EFAs and antioxidants are needed.