Idiosyncrasy definition

Histamine release by suxamethonium was inhibited not only with acetylcholine, as mentioned above, but also with nicotinic antagonists. These findings (Fig. 6) suggest that histamine release by suxamethonium is related to its pharmacological site of action at nicotinic receptors. This may be in favour of reaction and histamine release, both being due to idiosyncrasy rather than to allergy, but it is extremely difficult to draw definite conclusions. 

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