The dose of the fluid extract (Extractum Cocae Fluidum,) is from 1/2 to 2 drachms. The dose of Cocaine is from 1/4 to 1/2

1 / grain. The dose of the Hydrochlorate of Cocaine is 1/6 to 1/2 grain.

A point of considerable importance in using cocaine hypoder-mically is to make use of a perfectly aseptic syringe ; for frequently in cases where the drug is so used and suppuration follows, it is 23 the fault of want of cleanliness in this particular, and not to the employment of the drug.

The quantity of cocaine required to produce anaesthesia varies with the operation and its extent; as a rule for ordinary minor operations from 25 to 40 minims of a four per cent solution are needed. The length of time necessary for the production of local anaesthesia or insensibility under cocaine varies from three to ten minutes.

Dr. Bier, of Kiel, quite recently, claimed that by throwing small quantities of very dilute cocaine solutions into the spinal canal, the nerves are affected at their roots, and the lower part of the body is rendered completely insensible to pain, the effect lasting about three-quarters of an hour. Very curiously, perception of heat and cold, as well as of touch and pressure, are not affected. Severe operations, it is claimed, have been satisfactorily performed, but the after-effects - such as dizziness, severe headache and vomiting - are quite as unpleasant and more prolonged than those following chloroform and ether.

Dental Uses

In operations in the mouth, affecting the mucous membrane and the immediately subjacent tissues, the salts of cocaine have proved efficient for their local anaesthetic and anodyne effects. But for operations on deep-seated tissues, such as are involved in the extraction of teeth, the action of pure cocaine is not certain in its practicable benefits. Cocaine has, however, proven very efficient in relieving the pain of the surgical treatment of alveolar pyorrhoea, the extirpation of the pulps of teeth, and, in some cases, that of hypersensitive dentine. Exposed pulps are rendered less painful after being treated with a five per cent. solution of cocaine, to which, in some cases, morphine has been added. In some cases also, it is claimed, highly inflamed pulps have been successfully capped, as an experiment, with a paste of cocaine and glycerine, although, as was foreseen, the anaesthetic did not arrest the course of the pulpitis. In treating hypersensitive dentine, the more sensitive the structure the stronger the solution of cocaine to be employed. The pure cocaine in the form of crystals, of the hydrochlorate or other salts, has proven efficient when applied to hypersensitive dentine. For the extirpation of pulps of teeth, it is recommended first to anaesthetize the pulps superficially, with a paste of cocaine and glycerine, and then to introduce, by means of a syringe, a twenty per cent. solution of cocaine directly on the exposed portion of the pulp, when it can be removed with a nerve extractor without causing any pain. Dr. John S. Marshall, from his experiments with the pills of citrate of cocaine, found that under favorable circumstances, the citrate, in such a form, produces anaesthesia, when applied to sensitive dentine, in from five to ten minutes, and that the obtunding effect is of a duration sufficient for the preparation of the cavity. He was also able to extirpate the pulp of the tooth, after the citrate had been applied, in from three to twelve minutes. In using the citrate in the form of pills, one pill is introduced into the sensitive cavity, and, after being secured with a pledget of cotton, moistened in tepid water, is permitted to remain from five to twelve minutes. Dr. Marshall suggests the use of granules, containing one-sixteenth of a grain of pure citrate of cocaine, instead of pills containing glycerine and saccharine matters. A solution of the salts of cocaine has also been sub-cutaneously injected, with favorable results, for the relief of the pain resulting from periodontitis and hypercementosis; and Dr. Hillischer recommends the rubbing in of cocaine, either in substance or in concentrated solution, after the epithelium has been macerated with tincture of iodine, to promote absorption, and thus relieve the pain of chronic periodontitis; also the repeated application of the concentrated solution to relieve the ulcers of thrush, aphthae, etc. In the surgical treatment of alveolar pyorrhoea, the pain may be relieved by first applying dilute alcohol to the gums, by means of a camel's-hair brush, and then in the same manner, a ten per cent. solution of cocaine, repeating the application of the cocaine once or twice during the space of five minutes. The slowness of the action of cocaine is a great objection to its use as an anaesthetic.

The four per cent. or five per cent. solution applied to a tooth unprotected by a rubber dam (as the rubber prevents the anaesthetic action of the agent), for the space of twenty minutes, repeating the application if necessary, is recommended by Dr. Thompson. Dr. A. W. Harlan recommends a solution composed of cocaine hydrochlorate ten grains, in sulphuric ether, ninety minims, which is to be applied for four or five minutes, for the painless extirpation of an exposed pulp.

Dr. Harper recommends the following method for removing pulps of teeth by the use of crystals of cocaine: "Take a drop of the oil of cloves and add enough cocaine to make a thick paste and introduce it into the pulp, after having first put the rubber dam on the tooth; then with a broach slowly work it down ; with a bur open up the opening slowly, and in ten or fifteen minutes the pulp may be removed from any of the anterior teeth." Where arsenic has been applied to the pulp and the patient returns with pain, relief will be obtained from the application of cocaine.

Herbst's Obtundent consists of a saturated solution of cocaine hydrochlorate in chemically pure sulphuric acid, to which sulphuric ether is added to the point of saturation, the excess of the ether floating upon the surface and evaporating. Several applications are necessary to produce anaesthetic effects, and seventy grains of cocaine hydrochlorate are required to saturate two drachms of the sulphuric acid.