Cocaine (benzoylmethylecgonine) is a crystalline tropane alkaloid that is obtained from the leaves of the coca plant.[5] The name comes from "coca" in addition to the alkaloid suffix -ine, forming cocaine. It is a stimulant of the central nervous system and an appetite suppressant. Specifically, it is a serotonin-norepinephrine-dopamine reuptake inhibitor, which mediates functionality of such[clarification needed] as an exogenous catecholamine transporter ligand. Because of the way it affects the mesolimbic reward pathway, cocaine is addictive.[6]
Its possession, cultivation, and distribution are illegal for non-medicinal and non-government sanctioned purposes in virtually all parts of the world. Although its free commercialization is illegal and has been severely penalized in virtually all countries, its use worldwide remains widespread in many social, cultural, and personal settings.
Coca leaf
Coca leaf in Bolivia
For over a thousand years South American indigenous peoples have chewed the coca leaf (Erythroxylon coca), a plant that contains vital nutrients as well as numerous alkaloids, including cocaine. The leaf was, and is, chewed almost universally by some indigenous communities—ancient Peruvian mummies have been found with the remains of coca leaves and pottery from the time period depicts humans, cheeks bulged with the presence of something on which they are chewing.[7] There is also evidence that these cultures used a mixture of coca leaves and saliva as an anesthetic for the performance of trepanation.[8]
When the Spanish arrived in South America, most at first ignored aboriginal claims that the leaf gave them strength and energy, and declared the practice of chewing it the work of the Devil. But after discovering that these claims were true, they legalized and taxed the leaf, taking 10% off the value of each crop.[9] In 1569, Nicolás Monardes described the practice of the natives of chewing a mixture of tobacco and coca leaves to induce "great contentment":
“ [...when they wished to] make themselves drunk and [...] out of judgment [they chewed a mixture of tobacco and coca leaves which ...] make them go as they were out of their wittes [...][10] ”
In 1609, Padre Blas Valera wrote:
“ Coca protects the body from many ailments, and our doctors use it in powdered form to reduce the swelling of wounds, to strengthen broken bones, to expel cold from the body or prevent it from entering, and to cure rotten wounds or sores that are full of maggots. And if it does so much for outward ailments, will not its singular virtue have even greater effect in the entrails of those who eat it? ”
Isolation
Although the stimulant and hunger-suppressant properties of coca had been known for many centuries, the isolation of the cocaine alkaloid was not achieved until 1855. Various European scientists had attempted to isolate cocaine, but none had been successful for two reasons: the knowledge of chemistry required was insufficient at the time, and the cocaine in the plant was damaged because coca does not grow in the Eurasian region and ruined easily amidst transcontinental shipping.
The cocaine alkaloid was first isolated by the German chemist Friedrich Gaedcke in 1855. Gaedcke named the alkaloid "erythroxyline", and published a description in the journal Archiv der Pharmazie.[11]
In 1856, Friedrich Wöhler asked Dr. Carl Scherzer, a scientist aboard the Novara (an Austrian frigate sent by Emperor Franz Joseph to circle the globe), to bring him a large amount of coca leaves from South America. In 1859, the ship finished its travels and Wöhler received a trunk full of coca. Wöhler passed on the leaves to Albert Niemann, a Ph.D. student at the University of Göttingen in Germany, who then developed an improved purification process.[12]
Niemann described every step he took to isolate cocaine in his dissertation titled Über eine neue organische Base in den Cocablättern (On a New Organic Base in the Coca Leaves), which was published in 1860—it earned him his Ph.D. and is now in the British Library. He wrote of the alkaloid's “colourless transparent prisms” and said that, “Its solutions have an alkaline reaction, a bitter taste, promote the flow of saliva and leave a peculiar numbness, followed by a sense of cold when applied to the tongue.” Niemann named the alkaloid “cocaine”—as with other alkaloids its name carried the “-ine” suffix (from Latin -ina).[12]
The first synthesis and elucidation of the structure of the cocaine molecule was by Richard Willstätter in 1898.[13] The synthesis started from tropinone, a related natural product and took five steps.
Medicalization
With the discovery of this new alkaloid, Western medicine was quick to exploit the possible uses of this plant.
In 1879, Vassili von Anrep, of the University of Würzburg, devised an experiment to demonstrate the analgesic properties of the newly-discovered alkaloid. He prepared two separate jars, one containing a cocaine-salt solution, with the other containing merely salt water. He then submerged a frog's legs into the two jars, one leg in the treatment and one in the control solution, and proceeded to stimulate the legs in several different ways. The leg that had been immersed in the cocaine solution reacted very differently than the leg that had been immersed in salt water.[14]
Carl Koller (a close associate of Sigmund Freud, who would write about cocaine later) experimented with cocaine for ophthalmic usage. In an infamous experiment in 1884, he experimented upon himself by applying a cocaine solution to his own eye and then pricking it with pins. His findings were presented to the Heidelberg Ophthalmological Society. Also in 1884, Jellinek demonstrated the effects of cocaine as a respiratory system anesthetic. In 1885, William Halsted demonstrated nerve-block anesthesia,[15] and James Corning demonstrated peridural anesthesia.[16] 1898 saw Heinrich Quincke use cocaine for spinal anesthesia.
Today, cocaine has very limited medical use. See the section Cocaine as a local anesthetic
Popularization
In 1859, an Italian doctor, Paolo Mantegazza, returned from Peru, where he had witnessed first-hand the use of coca by the natives. He proceeded to experiment on himself and upon his return to Milan he wrote a paper in which he described the effects. In this paper he declared coca and cocaine (at the time they were assumed to be the same) as being useful medicinally, in the treatment of “a furred tongue in the morning, flatulence, [and] whitening of the teeth.”
Pope Leo XIII purportedly carried a hipflask of the coca-treated Vin Mariani with him, and awarded a Vatican gold medal to Angelo Mariani.
A chemist named Angelo Mariani who read Mantegazza’s paper became immediately intrigued with coca and its economic potential. In 1863, Mariani started marketing a wine called Vin Mariani, which had been treated with coca leaves, to become cocawine. The ethanol in wine acted as a solvent and extracted the cocaine from the coca leaves, altering the drink’s effect. It contained 6 mg cocaine per ounce of wine, but Vin Mariani which was to be exported contained 7.2 mg per ounce, to compete with the higher cocaine content of similar drinks in the United States. A “pinch of coca leaves” was included in John Styth Pemberton's original 1886 recipe for Coca-Cola, though the company began using decocainized leaves in 1906 when the Pure Food and Drug Act was passed. The actual amount of cocaine that Coca-Cola contained during the first twenty years of its production is practically impossible to determine.[citation needed]
In 1879 cocaine began to be used to treat morphine addiction. Cocaine was introduced into clinical use as a local anesthetic in Germany in 1884, about the same time as Sigmund Freud published his work Über Coca, in which he wrote that cocaine causes
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