The antiparkinsonian effects of dexetimide were investigated in patients under neuroleptic maintenance therapy.
All patients were receiving orphenadrine 150 mg/day as corrective medication. The trial was conducted in two stages: an open study including 40 patients and a double-blind, placebo-controlled study including 20 patients who had responded best during the open phase.
Evaluation was carried out using a 10-point rating scale for extrapyramidal symptoms and an 8-points rating scale for possible side-effects.
The optimum daily dose of dexetimide ranged between 0.5 and 3 mg. In the open study, dexetimide was found to be significantly more effective than orphenadrine in controlling extrapyramidal symptoms. The overall score for side-effects was similar for botte drugs, with a significant differente to the disadvantage of deretimide for item 'dry mouth'. During the double-blind, patients in the placebo group had significantly higher scores than during the previous treatment with dexetimide.