Cocaine, also known as coke, is a strong stimulant most frequently used as a recreational drug.[13] It is commonly snorted, inhaled as smoke, or dissolved and injected into a vein.[12] Mental effects may include loss of contact with reality, an intense feeling of happiness, or agitation.[12] Physical symptoms may include a fast heart rate, sweating, and large pupils.[12] High doses can result in very high blood pressure or body temperature.[14] Effects begin within seconds to minutes of use and last between five and ninety minutes.[12] Cocaine has a small number of accepted medical uses such as numbing and decreasing bleeding during nasal surgery.[15]

Cocaine is addictive due to its effect on the reward pathway in the brain.[13] After a short period of use, there is a high risk that dependence will occur.[13] Its use also increases the risk of stroke, myocardial infarction, lung problems in those who smoke it, blood infections, and sudden cardiac death.[13][16] Cocaine sold on the street is commonly mixed with local anesthetics, cornstarch, quinine, or sugar, which can result in additional toxicity.[17] Following repeated doses a person may have decreased ability to feel pleasure and be very physically tired.[13]

Cocaine acts by inhibiting the reuptake of serotonin, norepinephrine, and dopamine.[13] This results in greater concentrations of these three neurotransmitters in the brain.[13] It can easily cross the blood–brain barrier and may lead to the breakdown of the barrier.[18][19] In 2013, 419 kilograms were produced legally.[20] It is estimated that the illegal market for cocaine is 100 to US$500 billion each year.[13] With further processing, crack cocaine can be produced from cocaine.[13]

Cocaine is the second most frequently used illegal drug globally, after cannabis.[21] Between 14 and 21 million people use the drug each year.[13] Use is highest in North America followed by Europe and South America.[13] Between one and three percent of people in the developed world have used cocaine at some point in their life.[13] In 2013, cocaine use directly resulted in 4,300 deaths, up from 2,400 in 1990.[22] It is named after the coca plant from which it is isolated.[12] The plant's leaves have been used by Peruvians since ancient times.[17] Cocaine was first isolated from the leaves in 1860.[13] Since 1961, the international Single Convention on Narcotic Drugs has required countries to make recreational use of cocaine a crime.[23]