Methadone-Related Delirium: Prevalence, Causes, and Outcomes.

Goals consist of determining 5-year prevalence and recurrence of methadone-related delirium (MRD), along with causes, treatments, and outcomes. Sample comprised 81 patients in methadone maintenance treatment. Criteria for MRD encompassed delirium with high methadone serum levels plus alleviation of delirium upon lowering methadone serum levels. MRD occurred in 14 cases who had 25 episodes. MRD precipitants included physician prescribing (i.e., excessive methadone or medications slowing methadone metabolism), drug misuse, and renal-fluid alterations. Social affiliation (housing with family, intimate partner) reduced MRD; employment increased MRD. Recovery occurred in 23/25 episodes of MRD; two episodes progressed to dementia. Obtaining serum methadone levels fostered prompt recognition.