coke, blow, candy, crack, jack, jimmy, rock, nose candy, whitecoat. Cocaine causes a sense of energy, alertness, talktiveness, and well-being users find pleasurable. At the same time, they experience sympathetic nervous system stimulation, including an increased heart rate, and blood pressure and dilation of bronchioles (breathing tubes) in the lungs. When injected and smoked, these drugs cause an intense feeling of euphoria.

Cocaine is a substance that is found in the leaves of a shrubby plant (Erythoxylum coca) commonly found growing wild in Peru, Bolivia, and Ecuador and cultivated in many countries. The natives of South America used cocaine as an important part of their daily lives: they chewed cocaine leaves for increased alertness and endurance.

Cocaine as it is known today was first synthesised in 1855 although it was not until 1880 that its effects were recognised by the medical world. Cocaine is an alkaloid derivative of the coca plant, generally available in powder form which can be zero to 90% pure, and "rock" which is more common and generally 25% to 40% pure. Cocaine is often cut with other substances, such as lactose (milk sugar) mannitol (barley laxative), or amphetamines.

The leaves of the coca plant are made into a paste and its contents heated with hydrochloric acid to produce cocaine hydrochloride. This most common form of cocaine is a white, crystalline powder, freely soluble in water, but rarely used internally or injected. The most popular method of use is to separate the powder into fine "lines" of approximately 1/4 gram, 4-6 inches long. A small straw is then used to "snort" the cocaine into the nose.

Cocaine is best known for it's ability to increase focus and mental alertness, eliminate fatigue and decrease the appetite. Cocaine users are often talkative, full of energy, confident to the point of being restless and fidgety.

Cocaine initiates all the symptoms of the fight-or-flight syndrome: it increases the heart rate and blood pressure, constricts blood vessels, dilates the bronchioles (breathing tubes), increases blood sugar, and generally prepares the body for emergency. It also improves the symptoms of asthma and breaks down fat to create energy and therefore contributes to weight loss. It can have excessive effects on the heart, leading to a disordered heart beat or eventually, failure of the cardiovascular system and can also increase body temperature to a dangerous extent.

Euphoria, blood pressure, appetite and attention are all regulated by a related group of neurotransmitters: the biogenic amines or monoamine neurotransmitters. Normally, these sensations are caused when neurons communicate with each other and fire impulses through the brain via the neurotransmittors. Monoamine neurotransmittors release their neurotransmittors into the synaptic cleft and act on their receptors. Then the monoamine neurons recapture them by pumping them back into the neuron. This is how the neurons stop the transmission. Stimulants interfere with the recapture mechanism by blocking the sites where the neurotransmitters are normally taking, leaving them to stay in the synaptic cleft longer and continue to stimulate the receptors.

When taken in larger amounts and upon prolonged use, cocaine can produce depression, anxiety, irritability, sleep problems, chronic fatigue, mental confusion, paranoia, and convulsions that can cause death. The prolonged or compulsive use of cocaine in any of its purified forms can cause severe personality disturbance, inability to sleep and loss of appetite. A toxic psychosis can develop involving paranoid delusions and disturbing tactile hallucinations in which the user feels insects crawling under the skin.

sources:
Kuhn, Cynthia, Scott Swartzwelder and Wilkie Wilson. Buzzed : the straight facts about the most used and abused drugs from alcohol to ecstasy. New York: W.W. Norton, 1998.

portions reprinted from:
"methamphetamine" Britannica.com. Vers. 2001
1999-2001. Encyclopædia Britannica.
1 Sep. 2000
(http://www.britannica.com/eb/article?eu="24947"&tocid="0"&query=cocaine)