Muscle relaxants are often used during surgery procedure because it allows surgery to be conducted with ease. These muscle relaxants (neuromuscular blocking agents) a generally categorized into depolarising and non-depolarising agents due to their mode of actions. The most common depolarising neuromuscular blocking agent is Suxamethonium. It produces an important biochemical effect, which causes depolarisation and rapid relaxation of the muscles. Suxamethonium is been used commonly due to its rapid onset and short duration of action despite its complications such as hyperkalemia, muscle pain, anaphylaxis and life-threatening condition malignant hyperthermia. Non-depolarising agents, however, have a different mode of action compared to the depolarizing agents because this agent exhibits the effects by competitively blocking the postsynaptic receptors at the neuromuscular junction. They produce longer effects however require very close monitoring and need special agents such as neostigmine to reverse the action of the non-depolarising agent towards the end of the procedure.