Suxamethonium is:

Suxamethonium is Succinyl choline that is a depolarising blocker. Suxamethonium chloride, also known assuxamethonium or succinylcholine, is a medication used to cause sho-term paralysis as pa of general anesthesia. This is done to help with tracheal intubation or electroconvulsive therapy. It is given either by injection into a vein or muscle. From KD Tripati 7th edition Page no 345