Benzodiazepine withdrawal delirium is thought to be uncommon. Only two clear reports of alprazolam withdrawal appear in the literature, but the use of this drug is expected to increase because of its recent approval for the treatment of panic disorder. We report on a patient with severe alprazolam withdrawal delirium that developed immediately after an accidental reduction of the dose. This case demonstrates importance of clinician awareness of the previous use of alprazolam in individual patients, especially in hospital settings where free patient use of drugs is prohibited.