Cocaine is an alkaloid of erythroxylon coca and cocaine hydrochlorate is produced by the action of hydrochloric acid on cocaine. It is soluble in alcohol, ether and water, has a bitter taste, no odor, is of a white color and is in form of crystals. It is mostly used hypodermically; the strength varies from 2% to 4% solution, according to conditions and susceptibility of the patient.
Physiological action: Used internally it acts as a stimulant to the brain, in medicinal doses, and causes a feeling of strength and endurance and even exhilaration. After this effect is worn off, depression and general lassitude follow. In toxic doses the pulse, which may be strong and rapid, will become rapid, small and intermittent; respiration becomes slow and shallow with a feeling of tightness around the chest, cold and clammy skin, dilated pupils: a feeling as if death was near; inco-ordination of muscles, hallucinations, delirium and death resulting from paralysis of the sensory spinal, respiratory and cardiac motor ganglia. Locally as an anesthetic it paralyses the terminal nerves, and, by conveying this paralyzing action to the nerve centers, we can readily see why at times it becomes a source of danger, especially if near the brain centers. When injected it produces an anemia followed by coldness and finally by loss of sensation. It has little effect on the skin if unbroken; but is very easily absorbed by the mucous membrane. As a local anesthetic in minor operations, ophthalmic practice and ear and nose practice it is extensively used and with success; but its effect should be carefully watched as some persons are very susceptible to its influence. Surgical wounds will not heal so well where cocaine has been used, and for that reason it is objectionable in many cases.
Use: As stated before, it is quite extensively used as a local anesthetic in minor operations. In epistaxis a 1% solution sprayed into the nose will often promptly stop the bleeding. No matter in what form and how it is used its action should always be very carefully watched, and, if any symptoms of poisoning appear, it should be discontinued at once and if necessary its effects counteracted. It should not be used internally unless positively necessary; nor be used any length of time hypodermically to avoid the danger of forming the cocaine habit. Solutions made of cocaine will not keep, but a grain or two of boracic acid added to ½ ounce of a 1 to 4% solution will preserve it for some time. Of late cocaine has been injected into the spine in the lumbar region in major operation of the legs and even of the pelvic organs. This needs further investigation.