Cocaine is natural coca alkaloid obtained from leaves of coca (= cocca) plant-Erythroxylum coca (Family Erythroxylaceae) - a South American plant growing on the foot hills of Andes. Its chemical formula is C17H21NO4. Cocaine is commonly called coke or crack. It is bitter, white, crystalline powder and called snow, sniff, crack, coke, princess, Big C. Cocaine has vasoconstrictor properties and therefore, is a good local anaesthetic. It is taken by snorting. It is a powerful CNS stimulant. It induces a sense of well-being and pleasure and delays fatigue. Its overdose causes headache, convulsions, insomnia, respiratory or cardiac failure and may lead to mental disorder. Excessive dosage of cocaine causes hallucinations.