Toxic-induced parkinsonism

Abstract

A large number of neurotoxins have been linked with secondary parkinsonism including metals, organic solvents and illicit drugs (Table 21.1). Manganese was the first substance linked with parkinsonism (Couper Br Ann Med Pharm 1:41-42, 1837), but the precise cause of its toxicity remains undetermined. An outbreak of 1-methyl-4-phenyl-1,2,5,6-tetrahydropyridine (MPTP) parkinsonism caused by preparation of a designer drug MPPP in California provided several clues to the possible pathogenesis of Parkinson’s disease and the development of a non-human primate animal model for drug testing (Langston and Ballard Science 219:979-980, 1983). Improved public health measures designed to prevent exposure to neurotoxins is the most important need as apart from chelation therapy or the promotion of excretion of the toxin by haemodialysis, no efficacious symptomatic treatments are available.