A cholinergic crisis is an over-stimulation at a neuromuscular junction due to an excess of acetylcholine (ACh), as of a result of the inactivity (perhaps even inhibition) of the AChE enzyme, which normally breaks down acetylcholine. This is a consequence of some types of nerve gas, (e.g. sarin gas). In medicine, this is seen in patients with myasthenia gravis who take too high a dose of their anticholinesterase treatment medications, or seen in some surgical cases, when too high a dose of a cholinesterase inhibitor is given to reverse surgical muscle paralysis.
As a result of cholinergic crisis, the muscles stop responding to the bombardment of ACh, leading to flaccid paralysis, respiratory failure, and other signs and symptoms reminiscent of organophosphate poisoning. Other symptoms include increased sweating, salivation, bronchial secretions along with miosis. This crisis may be masked by the concomitant use of atropine along with anticholinesterase inhibitors in order to prevent side effects. Flaccid paralysis resulting from cholinergic crisis can be distinguished from myasthenia gravis by the use of the drug edrophonium (Tensilon), which worsens the paralysis caused by cholinergic crisis, but strengthens the muscle in the case of myasthenia gravis.(Edrophonium is an anticholinesterase hence increases the concentration of acetylcholine present). Cholinergic crisis can be treated with antimuscarinic drugs like atropine.
Famous quotes containing the word crisis:
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—Novalis [Friedrich Von Hardenberg] (1772–1801)