"Cocaine is a sympathomimetic drug with CNS stimulant and euphoriant properties. High doses can cause panic, schizophrenic-like symptoms, seizures, hyperthermia, hypertension, arrhythmias, stroke, aortic dissection, intestinal ischemia, and MI. Toxicity is managed with supportive care, including IV benzodiazepines (for agitation, hypertension, and seizures) and cooling techniques (for hyperthermia). Withdrawal manifests primarily as depression, difficulty concentrating, and somnolence (cocaine washout syndrome).
"Most cocaine users are episodic recreational users. However, about 25% (or more) of users meet criteria for abuse or dependence. Use among adolescents has declined recently. Availability of highly biologically active forms, such as crack cocaine, has worsened the problem of cocaine dependence. Most cocaine in the US is about 50 to 60% pure; it may contain a wide array of fillers, adulterants, and contaminants.
"Most cocaine in the US is volatilized and inhaled, but it may be snorted, or injected IV. For inhalation, the powdered hydrochloride salt is converted to a more volatile form, usually by adding NaHCO3, water, and heat. The resultant precipitate (crack cocaine) is volatilized by heating (it is not burned) and inhaled. Onset of effect is quick, and intensity of the high rivals IV injection. Tolerance to cocaine occurs, and withdrawal from heavy use is characterized by somnolence, difficulty concentrating, increased appetite, and depression. The tendency to continue taking the drug is strong after a period of withdrawal."


"Cocaine," The Merck Manual for Health Care Professionals, Special Subjects, Drug Use and Dependence, Cocaine (Merck & Co. Inc.: July 2008), last accessed Dec. 13, 2012.