From a review of the clinical literature, the authors determined that
the medical symptoms of neuroleptic withdrawal occurred more frequently
with neuroleptics having potent anticholinergic effects than with those
having weak anticholinergic actions. When antiparkinsonian agents were not
simultaneously withdrawn, there was a striking difference between these two
categories of neuroleptics. Experiments with mice showed that withdrawal of
haloperidol, a neuroleptic with weak anticholinergic effects, produced
subsensitivity (depression of locomotor activity and seizure thresholds) to
the cholinergic effects of physostigmine. These findings support the theory
that the medical side effects of neuroleptic withdrawal are due to rebound
cholinergic hypersensitivity associated with the anticholinergic actions of
these drugs, rather than being related to their dopamine-blocking
activity.Abstract Teaser