Lack of major olfactory dysfunction in MPTP-induced parkinsonism

The olfactory function of 6 patients whose parkinsonism was the result of intravenous administration of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) was compared to that of 12 age-matched patients with idiopathic Parkinson's disease (PD) and 10 age-matched normal control subjects. Unlike their PD counterparts, the olfactory test scores of patients with MPTP-induced parkinsonism, did not differ significantly from those of control subjects. These findings suggest that MPTP induced parkinsonism, unlike idiopathic PD, is unaccompanied, on average, by major alterations in the ability to smell.