Dexmedetomidine is a sedative medication used by intensive care units and anesthesiologists, and is marketed under the brand name Precedex (Hospira, Inc.) in the United States. It is relatively unique in its ability to provide sedation without causing respiratory depression. Like clonidine, its mechanism of action is agonism of alpha-2 receptors in certain parts of the brain. It is the S-enantiomer of medetomidine.

Dexmedetomidine has sedative, analgesic, sympatholytic, and anxiolytic effects that blunt many of the cardiovascular responses in the perioperative period. It reduces the volatile anesthetic, sedative and analgesic requirements of the patient without causing significant respiratory depression.

Recent research has suggested dexmedetomidine to be an effective treatment for the dangerous cardiovascular symptoms of cocaine intoxication and overdose. It also seemed to be superior to lorazepam for ventilated patients in the intensive care unit. Compared to midazolam, dexmedetomidine was similarly effective for sedation, but shortened the time to extubation, was associated with less delirium, and experience more bradycardia and less tachycardia and hypertension.