Delirium due to intoxication with quetiapine: a systematic literature review

Quetiapine is a frequently prescribed antipsychotic and therefore often used in overdose. Delirium (with anticholinergic delirium as a specific condition) is described as a serious complication of quetiapine intoxication. AIM: To assess the scientific literature on delirium as a side effect of quetiapine intoxication: incidence, symptoms and treatment. METHOD: A systematic Medline literature search. RESULTS: The systematic literature search resulted in 36 papers: 11 cohort studies, 24 case reports (22 papers) and 3 review papers. The reported incidence varied greatly, probably due to different quality of assessment. The clinical picture is characterized by a varying combination of peripheral and central symptoms, with agitation occurring frequently. Treatment is mainly supportive. Physostigmine is described as a specific treatment for anticholinergic delirium/toxidrome. Effectiveness of other pharmacological interventions remains unclear. CONCLUSION: Delirium due to quetiapine intoxication is described repeatedly. Presumably there is an underreporting of this condition and associated symptoms. Better knowledge could lead to better detection and treatment.