Prolonged anticholinergic delirium following antihistamine overdose.

Objective: A case of anticholinergic delirium in a female adolescent is described, exploring the pharmacokinetic reasons for the prolonged time course and reviewing the management provided.

Conclusion: A 14 year old female hospitalised for depression ingested large quantities of promethazine and cyproheptadine. A severe anticholinergic delirium ensued which resolved after six days, much longer than the expected duration.