The effect of R-(-)-deprenyl in de novo parkinsonian patients pretreated with levodopa and decarboxylase inhibitor correlated to depression and MHPG, HIAA and HVA levels in the cerebrospinal fluid.

1. The effectiveness and tolerability of deprenyl as an adjunct in the therapy of parkinsonism was studied in a double-blind trial comprising 30 de novo patients. 2. Two thirds of the cases that could be evaluated showed a statistically significant improvement while on adjuvant deprenyl therapy. 3. The improvements are shown in the replugging test, a subtest of the Motor Performance Test, and on the Columbia University Rating Scale. 4. There is no statistically significant correlation between improvement of motor response and depression. 5. Deprenyl seems to be less effective in patients with low contents of HIAA and HVA in the cerebrospinal fluid.