Cocaine is both a central nervous system stimulant and a topical anaesthetic. It is found in the leaves of the Erthroxylum coca plant. It is generally used either powder cocaine, or freebase/crack cocaine which produce much stronger effect; he term "Crack" is alternately used to refer to street quality freebase cocaine. Powdered cocaine is generally insufflated (snorted) and crack / freebase cocaine is generally smoked. Smoking freebase cocaine causes a strong, short-lived peak of about 3-5 minutes, while snorting cocaine provides a lower high with major effects lasting closer to 15 - 30 minutes.
The effects vary with dose and the tolerance of the user. Cocaine increases alertness, wakefulness, elevates the mood, increases athletic performance, decreases fatigue, clearer thinking, increases concentration, increases energy, increased irritability, insomnia, restlessness. With high doses one may exhibit a pattern of psychosis with confused and disorganized behavior, irritability, fear, paranoia, hallucinations, and may become extremely antisocial and aggressive.
Increases heart rate, blood pressure, body temperature, and sweating. Increases speed of respiration, dilates the pupils, decreased sleep and appetite.
Although cocaine does not cause dangerous physical addiction, discontinuing regular use can lead to a wide varieties of (very) unpleasant withdrawal and craving symptoms, including: intense cravings for more cocaine, hunger, irritability, apathy, depression, paranoia, suicidal ideation, loss of sex drive, insomnia or excessive sleep, dizziness, shaking, and/or feeling cold. Often, individuals simply take more cocaine to reduce these effects, leading to a pattern of habituation, dependence, and addiction.
Agitation, hostility, hallucinations, convulsions, high body temperature (hyperthermia),...