Pupillary constriction during haloperidol treatment as a predictor of relapse following drug withdrawal in schizophrenic patients.

Hypothesized that a measure of autonomic function, latency to maximum pupillary constriction, might predict relapse following withdrawal of medication in schizophrenic patients stabilized on haloperidol. Pupillary light reactions were recorded weekly from 19 chronic schizophrenic inpatients (aged 24–51 yrs) who were initially maintained on haloperidol and subsequently were withdrawn from medication under double-blind, placebo-controlled conditions. Patients were then classified as either relapsed or nonrelapsed (clinically stable) during the drug-free period. During the treatment phase, a shorter latency to maximum pupillary constriction significantly distinguished patients who were later to relapse from the nonrelapsers. The potential use of autonomic activity as an indicator of prodromal sensitivity was supported. (PsycInfo Database Record (c) 2020 APA, all rights reserved)