The coca bush has been cultivated for millennia, and 2000-year-old mummies from Nazca, Peru, have been found with small bags used for coca leaves in their possession (Stolberg, 2011). However, studies of drug use by pairs of fraternal twins suggest a significant genetic influence on the risk of developing cocaine abuse or dependence after use has begun. Coca leaf is the raw material for the manufacture of the drug cocaine, a powerful stimulant and anaesthetic extracted chemically from large quantities of coca leaves.  Because coca constricts blood vessels, it also serves to oppose bleeding, and coca seeds were used for nosebleeds. Coca leaves were transported back to Europe, where there was intermittent interest in their psychoactive properties.  Other names for this basifying substance are llipta in Peru and the Spanish word lejía, bleach in English.
The branches are straight, and the leaves, which have a green tint, are thin, opaque, oval, and taper at the extremities.
Besides cocaine, the coca leaf contains a number of other alkaloids, including methylecgonine cinnamate, benzoylecgonine, truxilline, hydroxytropacocaine, tropacocaine, ecgonine, cuscohygrine, dihydrocuscohygrine, nicotine, and hygrine. The first and most abundant harvest is in March after the rainy season, the second is at the end of June, and the third in October or November.
During this period, it is thought that coca leaves were chewed primarily to enhance physical performance and to decrease the need for food and rest. Several promising candidate genes have been identified, including those for dopamine receptors and the dopamine transporter, but no specific gene has been clearly linked with cocaine addiction. These included euphoria, increased attention, and the ability to work long hours without fatigue (Freud, 1884). It also can be used as a topical anesthetic, analgesic, diuretic, antispasmodic, antidepressant, and mood-elevating energizing tonic meant for normalizing bodily physiology (Manickam et al., 2014). ", In reaction to the 2007 Annual Report of the INCB, the Bolivian government announced that it would formally issue a request to the United Nations to unschedule the coca leaf of List 1 of the 1961 UN Single Convention. In the case of Argentina, it is legal only in some northwest provinces where the practice is so common that the state has accepted it. Because no compounds causing false-positive benzoylecgonine confirmation results have been reported, the interpretation of positive results should focus on explanations of cocaine introduction into the body. It is widely recognized for its action in enhancing work capacity, including the reduction of fatigue and the mitigation of thirst and hunger. During his speech to the General Assembly of the United Nations on September 19, 2006, he held a coca leaf in his hand to demonstrate its innocuity.. In the series of Aubrey-Maturin novels by Patrick O'Brien, set during the Napoleonic wars, Dr. Stephen Maturin, a naval physician, naturalist, and British intelligence agent discovers the use of coca leaves on a mission to Peru, and makes regular use of them in several of the later novels in the series. This reduction in 5-HT activity in the Nac could be observed for at least 12 hours (Parsons et al., 1995). The plants thrive best in hot, damp and humid locations, such as the clearings of forests; but the leaves most preferred are obtained in drier areas, on the hillsides.