Suxamethonium chloride

How it works

It binds and persistently activates nicotinic acetylcholine receptors at the neuromuscular junction, causing sustained depolarisation that, after initial fasciculation, prevents further muscle contraction.

Prescribing in practice

• It can cause life-threatening hyperkalaemia (notably in burns, major trauma, prolonged immobility and neuromuscular disease), malignant hyperthermia and, in those with pseudocholinesterase deficiency, markedly prolonged paralysis.
• It provides paralysis with no sedation or analgesia, so it must be used only with adequate anaesthesia and full airway and ventilation support.
• It commonly causes transient fasciculations, bradycardia (especially with repeated dosing or in children) and postoperative myalgia.

Monitoring

Monitor neuromuscular function, heart rhythm, oxygenation and temperature, remaining alert for hyperkalaemia and signs of malignant hyperthermia.

Counselling the patient

• Muscle aches after surgery are common and usually settle.
• Any known family history of problems or prolonged paralysis with anaesthesia should be reported to the team beforehand.

Evidence & guidelines

Its role in rapid sequence induction and its characteristic adverse effects are well established in anaesthetic practice and the SPC.