Let us first mention that cocaine (as well as amphetamines) is classified among the agents that are said to be central nervous system stimulants. While much of the information presented here also applies to dependence on alcohol and other drugs, there is some evidence that relates specifically to this family of chemicals.

We talk about substance abuse when the user repeatedly fails to fulfill his obligations at work, at school or at home. Or that he uses the substance despite physical danger, legal problems, or that it leads to social or interpersonal problems.

Dependence is characterized by tolerance, that is to say that the quantity of product necessary to obtain the same effect increases; withdrawal symptoms when stopping consumption, an escalation in the amounts and frequency of use. The user devotes a lot of his time to activities related to consumption, and he continues despite significant negative consequences.

Addiction is the act of compulsively seeking to consume a substance without regard to the negative consequences (social, psychological and physiological) of this use. Addiction seems to develop when repeated use of the substance changes certain neurons (nerve cells) in the brain. We know that neurons release neurotransmitters (various chemicals) to communicate with each other; each neuron can release and receive neurotransmitters (through receptors). It is believed that these stimulants cause a physiological modification of certain receptors in neurons, thus affecting their general functioning. These may never fully recover, even when stopping consumption. In addition, central nervous system stimulants (including cocaine) increase the levels of three neurotransmitters in the brain: Dopamine norepinephrine and the serotonin.

Dopamine. It is normally released by neurons to activate satisfaction and reward reflexes. Dopamine seems to be the main neurotransmitter linked to the problem of addiction, because satisfaction reflexes are no longer triggered normally in the brain in cocaine users.

The norépinéphrine. Normally released in response to stress, it causes the heart rate to increase, blood pressure to rise, and other hypertension-like symptoms. The subject experiences an increase in motor activity, with slight tremors in the extremities.

Serotonin. Serotonin helps regulate mood, appetite and sleep. It has a calming action on the body.

Recent research indicates that addictive drugs alter brain function in a way that persists after a person has stopped using. The health, social and work difficulties that often accompany the abuse of these substances do not necessarily end when the use is stopped. Experts see addiction as a chronic problem. Cocaine appears to be the drug with the greatest risk of addiction, due to its powerful euphoric effect and rapidity of action.

Origin of cocaine

The leaves of l’Erythroxyloncoca, a plant native to Peru and Bolivia, was chewed by Native American peoples and by conquistadors who appreciated its tonic effect. This plant also helped reduce the feeling of hunger and thirst. It was not until the middle of the XIX^e century that pure cocaine has been extracted from this plant. At that time, doctors used it as a tonic substance in many remedies. The harmful consequences were not known. Thomas Edison and Sigmund Freud are two famous users. Its presence as an ingredient in the original “coca-cola” drink is probably the best known (the drink has been exempt from it for several years).

Forms of cocaine

People who abuse cocaine use it in either of the following two chemical forms: cocaine hydrochloride and crack (freebase). Cocaine hydrochloride is a white powder that can be snorted, smoked, or dissolved in water and then injected intravenously. Crack is obtained by chemical transformation of cocaine hydrochloride to obtain a hard paste that can be smoked.

Prevalence of addiction

US National Institute on Drug Abuse (NIDA) says total number of cocaine and crack users has declined over the past decade¹. Cocaine overdose is the leading cause of drug-related admissions to hospitals in the United States and Europe. According to Canadian survey data, the prevalence of cocaine use among the Canadian population in 1997 was 0,7%², a rate identical to that of the United States. This is a decrease from the 3% rate in 1985, which was the maximum rate reported. According to these same surveys, men are twice as likely to report using cocaine than women.