Ann Oto Rhinol Laryn
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Almost a half century following attempts to ban its use, cocaine remains at the pinnacle of topical anesthesia in otolaryngology. To understand how nonaddicting synthetic substitutes such as procaine, dibucaine, tetracaine and lidocaine have not totally supplanted cocaine, requires an in-depth analysis of its unique pharmological properties, untoward effects and potential substitutes. Almost all of the reported cocaine deaths occurred after subcutaneous injection; when used topically, cocaine's toxicity has been confined to an occasional reaction. ⋯ Of other local anesthetics possessing topical effectiveness tetracaine is about six times more toxic than cocaine. Dibucaine is as toxic as tetracaine, and lidocaine, while relatively nontoxic, provides only a 15 minute duration of topical anesthesia. A review of cocaine and its potential substitutes thus leads to the conclusion that cocaine is still a vital and necessary instrument in the otolaryngologist's armamentarium, singularly providing excellent topical anesthesia of usable duration, vasoconstriction, and shrinkage of mucous membranes, all with a quite acceptable margin of safety.