Decamethonium Iodide (C 10): Some Observations on its Action Using Electromyography

Abstract

Decamethonium iodide produces an acetylcholine-like neuromuscular block. When electromyographic measurements were made of intact human voluntary muscles, wide variations were noted in the response to C 10. The effective dose of C 10 per kg. of body-wt. in conscious volunteers showed individual variation. Following intraven. injn., 2 groups of clinical signs and symptoms were noted; (1) initial involvement of the bulbar musculature[long dash]diplopia, ptosis and squint appeared within 15-20 sec. and started to disappear in 2 or 3 min. in the order of their onset. (2) The 2d group usually started about 4 min. after injn. as a rapidly increasing paralysis of peripheral musculature. C 10 stimulated not only muscle fiber activity but also motor unit activity. The blood flow to the limb altered the intensity of neuromuscular block. Subjects with myasthenia gravis were resistant to C 10.