Koller's cocaine local anesthesia

Cocaine had been isolated from coca leaves by the German chemist Albert Niemann, who published in 1860 and noticed that the crystals numbed his tongue. Suggestions that the drug might serve in surgery drew little interest. In the spring of 1884 the Viennese neurologist Sigmund Freud published Über Coca, a survey of the drug's effects that mentioned its numbing action only in its last paragraph; Freud hoped cocaine might cure morphine addiction.

Carl Koller, an intern in ophthalmology at Vienna's general hospital, had tried cocaine on himself with Freud. He knew that Schroff had reported in 1862 that it made the tip of the tongue and the throat insensible, and he asked whether it would do the same to other mucous membranes. He tested it in the eyes of animals, then in his own eyes and those of friends. A drop or two of a 2 percent solution of cocaine hydrochloride placed inside the lids made the conjunctiva and cornea insensible within moments, so that they could be touched or cut without pain. Animals given the drops did not blink when the cornea was touched.

The findings were announced at the congress of the Heidelberg Ophthalmological Society on 15 September 1884, and Koller's paper describing cocaine as a local anesthetic appeared on 18 September. He presented the work to the Medical Society of Vienna that October. Surgeons took it up for cataract extraction and iridectomy, and by October and November the Lancet was discussing it.

Other uses followed within months. William Halsted is credited with the first nerve blocks with cocaine, and in 1885 the American neurologist James Corning used it to produce the first spinal anesthesia. Halsted himself became addicted to the drug.