Abstract

Substituted aminoalkyl esters of carbazol-N-carboxylic acid have high local anesthetic activity, and in general, low toxicity. The presence of a urethane linkage appears to reduce the stimulant effect on the central nervous system that most local anesthetics possess, and to contribute a primary depressant effect. The most promising compound of the series (diethylaminoethyl carbazol-N-carboxylate, Carbacaine) has pressor activity, is absorbed slowly from subcutaneous tissues, and is detoxified more rapidly than cocaine. The use of the citrate as a soluble salt of carbacaine base, rather than the hydrochloride reduces the local irritation and confers stability.