Promethazine-induced delirium with perceptual abnormalities: are we thinking broadly when assessing patients?

There is limited information about promethazine-induced delirium with psychotic symptoms. The aim is to highlight the importance of taking a detailed history including medication use/abuse of both prescribed, illicit and over-the-counter preparations. This paper describes a patient who presented with delirium in the context of overuse of promethazine (Phenergan) which was initially missed. The patient was treated successfully, following the diagnosis of promethazine-induced delirium. Clinicians should be aware of assessing patients presenting with delirium to explore the possibility of over-the-counter medication misuse.