Substance abuse and movement disorders.

The complex relation between movement disorders and substance abuse is reviewed. First, we discuss the wide variety of movement disorders that occur as a direct consequence of acute use or withdrawal of drugs of abuse, such as alcohol, cocaine, heroin, amphetamine and methcathinone. Second, we describe the recent advances in the comorbid relationship between alcoholism and two movement disorders: essential tremor and myoclonus-dystonia. Lastly, we discuss the abuse potential of the dopaminergic agents, apomorphine and levodopa, in patients with Parkinson's disease.