Suxamethonium Donepezil

DONEPEZIL SUXAMETHONIUM Possible t efficacy of suxamethonium Suxamethonium is metabolized by cholinesterase parasympatho-mimetics inhibit cholinesterase and so prolong the action of suxamethonium Avoid co-administration. Ensure that the effects of suxamethonium have worn off before administering a parasympathomimetic to reverse non-depolarizing muscle relaxants. A careful risk-benefit analysis should be made before considering the use of suxamethonium for emergency anaesthesia in patients taking parasympathomimetics. The short half-life of edrophonium means that it can be used to diagnose suspected dual block with suxamethonium... 

The potential for interactions between donepezil and neuromuscular blocking agents has major implications for the anesthetic care of people taking donepezil (81,82,83). Prolonged paralysis resulting from an interaction of donepezil with suxamethonium has been reported (84,85). 

Heath ML. Donepezil, Alzheimer s disease and suxamethonium. Anaesthesia 1997 52 1018. 

Crowe S, Collins L. Suxamethonium and donepezil a cause of prolonged paralysis. Anaesthesiology 2003 98 574-5. 

Donepezil acts primarily as a reversible inhibitor of acetylcholinesterase with a half-life of over 70 hours. Prolonged paralysis lasting several hours and requiring postoperative mechanical ventilation in the intensive care unit has been reported after the use of suxamethonium in a patient taking long-term donepezil (285). 

A 72-year-old woman with a symptomatic hiatus hernia, osteoarthritis, and Alzheimer s disease was taking fluoxetine 20mg/day, donepezil hydrochloride 10 mg/ day, nimesulide 12.5mg/day, and omeprazole 20 mg/ day (288). There still was no twitch response to peripheral nerve stimulation 20 minutes after rapid-sequence induction of anesthesia with propofol 2.5mg/kg and suxamethonium 1 mg/kg. She then gradually developed a weak twitch response, and 50 minutes after induction of anesthesia four twitches with a fade were elicited by train-of-four stimulation. No additional medication was given and after the end of the procedure 10 minutes later she was extubated uneventfully. She refused further blood testing and so her plasma cholinesterase activity at that time is not known. However, her anesthetic notes from a previous operation did not reveal any problems with prolonged paralysis after suxamethonium. 

El-Kammah BM, El-Gafi SH, El-Sherbiny AM, Kader MMA. Biochemical and cUmcal stwfy for the role of tacrine as succinylcholine extender. J Egypt Med Assoc (1975) 58,559-67. Crowe S, Collins L. Suxamethonium and donepezil a cause of prolonged paralysis. 

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