The antiparkinsonian medication of 30 mental hospital patients was suddenly removed. Half the patients were then placed on placebo. During the ensuing month they did not manifest any significant change in extrapyramidal symptomatology. The other half of the patients received no replacement and during the ensuing month their extrapyramidal symptoms became significantly worse (p≤.02) than during the pretrial period. In other words, it was not the withdrawal of the actual antiparkinsonian compound, but the withdrawal of the factor of non-specific psychological treatment which brought about an increase of parkinsonian manifestations. It should be added that one-third of those who received no replacement whatsoever showed no increase of parkinsonian manifestations.These results would imply that potentially toxic antiparkinsonian medication was unnecessary in the vast majority of patients, although two-thirds would require some sort of non-specific psychological treatment to keep their symptoms in check.Abstract Teaser