This is one of a series of occasional articles on therapeutics for common or serious conditions, covering new drugs and old drugs with important new indications or concerns. The series advisers are Robin Ferner, honorary professor of clinical pharmacology, University of Birmingham and Birmingham City Hospital, and Albert Ferro, professor of cardiovascular clinical pharmacology, King's College London. To suggest a topic, please email us at practice@bmj.com.A 59 year old woman presents to the emergency department with an isolated anterior dislocation of her left shoulder after a fall. Other than controlled asthma, she is healthy. Her last meal was four hours before the injury. After adequate analgesia using intravenous fentanyl, and despite an initial attempt to reduce her dislocation using relaxation techniques, it becomes evident that she needs sedation to complete the procedure successfully.