Rocuronium (Zemuron, Esmeron) is an aminosteroid non-depolarizing neuromuscular blocker or muscle relaxant used in modern anaesthesia, to facilitate endotracheal intubation and to provide skeletal muscle relaxation during surgery or mechanical ventilation.


It was designed to be a weaker antagonist at the neuromuscular junction than pancuronium; hence its monoquaternary structure and its having an allyl group and a pyrrolidine group attached to the D ring quaternary nitrogen atom. Introduced in 1994, rocuronium has rapid onset, and intermediate duration of action.[1] It is marketed under the trade name of Zemuron in the United States and Esmeron in most other countries.

There is considered to be a risk of allergic reaction to the drug in some patients (particularly those with asthma), but a similar incidence of allergic reactions has been observed by using other members of the same drug class (non-depolarizing neuromuscular blocking drugs).[2]

The γ-cyclodextrin derivative sugammadex (trade name Bridion) has been recently introduced as a novel agent to reverse the action of rocuronium. [3]

On July 27, 2012, the State of Virginia replaced pancuronium bromide, one of the three drugs used in execution by lethal injection, with this drug.