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| Cocaine | |
| General | |
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| Chemical formula | C17H21NO4 |
| Molecular weight | 303.35 amu |
| CAS number | 50-36-2 |
| Other names | |
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Cocaine is a crystalline alkaloid that is obtained from the leaves of the coca plant. When consumed, it is a highly addictive drug that is a stimulant of the central nervous system. Though most often used recreationally for this effect, cocaine is also a topical anesthetic that is used in eye and nasal surgery.
For thousands of years, South American Indians chewed the coca leaf, a plant which contains vital nutrients as well as the cocaine alkaloid. The leaf was chewed almost universally in some tribes, but its habitual use did not lead to any of the negative consequences generally associated with habitual cocaine use today. It was an important source of nutrition and energy in a region that was lacking in other food sources and oxygen; the vitamins and protein present in the leaves, as much as the cocaine alkaloid, helped provide the energy and strength necessary for steep walks in this mountainous area.
When the Spaniards conquered South America, they at first ignored Indian 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. These taxes were for a time the main source of support for the Catholic Church in the region.
Although the stimulant and hunger-depressant properties of coca had been known for many centuries, the isolation of the cocaine alkaloid was not achieved until the summer of 1859. Although many scientists had attempted to isolate cocaine, no one had been successful for two reasons; the knowledge of chemistry required was insufficient at the time, and secondly, coca does not grow in Europe and is easily ruined during travel.
In 1856 Friederich 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 back 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 became the first person known to isolate cocaine. Niemann describes every step he took to isolate cocaine in a small work entitled On a New Organic Base, which earned him his Ph.D. and is now in the British Library. As with other alkaloids its name carried the "-ine" suffix.
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".
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. The ethanol in the wine acted as a solvent and extracted the cocaine from the coca leaves, altering the drink's effect. Later when Coca Cola was invented, cocaine was included in its ingredients. The only known measure of the amount of cocaine in Coca Cola was determined in 1902 as being as little as 1/400 of a grain per ounce of syrup. The actual amount of cocaine that Coca Cola contained is impossible to determine. Coca Cola discontinued the use of cocaine in the drink in 1929.
Cocaine was introduced into clinical use as a local anaesthetic in Germany in 1884. Although synthetic local anaesthetics are much more widely used today, cocaine is, to some degree, still in use in dentistry and ophthalmology. In 1879 it began to be used to treat morphine addiction. Cocaine use became very popular in the late 19th century, with many prominent figures praising its therapeutic and even recreational usage. Satisfied consumers of Mariani's cocaine-wine products included Ulysses S. Grant (whom Mariani claimed drank the elixir daily), Pope Leo XII, and "physicians to all the royal households of Europe." In 1885 the U.S. manufacturer Parke Davis and Co. sold cocaine in various forms, including cigarettes, powder, and even a cocaine mixture that could be directly injected into the user's veins with the included needle. The company promised that its cocaine products would "supply the place of food, make the coward brave, the silent eloquent and ... render the sufferer insensitive to pain."
By late Victorian times cocaine use had appeared as a 'vice' in literature, e.g., as the cucaine injected by Sir Arthur Conan Doyle's fictional Sherlock Holmes. By the turn of the twentieth century, the addictive properties of cocaine had become clear to many and the problem of cocaine abuse began to capture public attention in the United States. The dangers of cocaine abuse became part of a moral panic that was tied to the dominant racial and social anxieties of the day. In 1903 the American Journal of Pharmacy stressed that most cocaine abusers were "bohemians, gamblers, high- and low- class prostitutes, night porters, bell boys, burglars, racketeers, pimps, and casual laborers." In 1914 Dr. Christopher Koch of Pennsylvania's State Pharmacy Board made the racial innuendo explicit, testifying that "Most of the attacks upon the white women of the South are the direct result of a cocaine-crazed Negro brain." In the same year, the Harrison Narcotics Act heavily regulated cocaine, and it was officially outlawed as a narcotic in 1922.
Cocaine in its purest form is an off-white or pink chunky product. Cocaine appearing in powder is a salt, typically cocaine hydrochloride. Cocaine is frequently adulterated or "cut" with various powdery fillers to increase its volume; the substances most commonly used in this process are baking soda, sugars, such as lactose, inositol, and mannitol, and local anesthetics, such as lidocaine. Adulterated cocaine is often a white or off-white powder.
The colour of "crack" cocaine depends upon several factors including the origin of the cocaine used, the method of preparation — with ammonia or sodium bicarbonate, and the presence of impurities, but will generally range from a light off-white to a pale brown. Its texture will also depend on the factors which affect color, but will range from a crumbly texture, which is usually the lighter variety, to hard, almost crystalline nature, which is usually the darker variety.
"Freebase" is the street name given to cocaine that has been processed from cocaine hydrochloride to a ready–to–use free base for smoking. The practice of processing cocaine for smoking in this manner is expensive and requires high-quality cocaine.
The term "freebase" originated because of a mistranslation. In the early 1970s, peasants in Peru would smoke the pasty byproduct of the cocaine production process which was known as "baso," which translated as "paste". Rumors of this practice made it to Oakland, California, where "baso" was mistranslated as "base", thinking the Peruvians were smoking a cocaine "base" that had been reverse-engineered from pure cocaine. So "freebasing" was invented, in the belief that it was reproducing a practice imported from South America.
The smoking (or injection) of free-base cocaine has become popular because it eliminates some of the cutting agents and also produces a stronger high due to rapid absorption by the lungs.
Freebase cocaine is produced by first dissolving cocaine hydrochloride in water; a solvent (ether or ammonia) is added to release the cocaine alkaloid. A stronger base is then added to neutralize the acid content. The solvent will rise to the top and is drawn off; as the solvent evaporates, the cocaine salt oxidizes off, leaving the cocaine base.
Sometime in the early 1980s, probably in the Bahamas, it was discovered that expensive reverse–engineering was not necessary to make a smokable paste, and in fact one could process cocaine with ammonia or sodium bicarbonate (baking soda) and water, and then heating it to remove the hydrochloride; thus producing a form of cocaine that can be smoked — what has been since the mid–1980s been known as "rock" or "crack" cocaine. (The term "crack" refers to the crackling sound which is made when the mixture is heated, while "rock" refers to the physical appearance of the compound.)
Users originally began mixing cocaine with ammonia to test the purity of their product. This process removes any impurities from the cocaine and allows the user to determine the amount of pure cocaine remaining. No longer dependent on high–quality cocaine or an expensive chemical process, users now had an extremely cheap form of smokable cocaine. This new process became popular soon after a coup in Bolivia flooded the world market with cheap cocaine.
Crack cocaine, is often sold in small, inexpensive dosage units frequently known as "nickels" or "nickel rocks" (referring to the price of $5.00), and also "dimes" or "dime rocks" ($10.00). The quantity provided by a "nickel" or "dime" rock varies depending upon many factors, such as geographic location or availability.
Absorption is approximately 80% through the nasal membranes when cocaine powder is "snorted". The blood vessels limit absorption. Chronic use results in ongoing rhinitis and necrosis of the nasal membranes. Cellulose granulomas from adulterants have also been found in the lungs of recreational "sniffers".
The intravenous route of administration provides the highest blood levels of drug in the shortest time. Injection of cocaine produces an exhilarating rush, although the euphoria passes quickly as the liver rapidly metabolizes the drug. Besides the toxic effects of cocaine, there is also danger of circulatory emboli from the insoluble substances that may be used to cut the drug. Obviously, there is also a risk of serious infection associated with the use of contaminated needles.
Smoking is most often accomplished using a pipe made from a small glass tube about one-quarter inch in diameter and up to several inches long. These are sometimes called "straight shooters" and are frequently readily available at discount stores or smoke shops. They will sometimes contain a small paper flower and are promoted as a "rose".
A small piece of copper scouring pad — often called a "brillo", from the scouring pad of the same name — is placed into one end of the tube after having the copper plating burned off. It then serves as a crude filter to prevent the "rock" from being sucked into the mouth when smoking, while allowing the smoke to pass uninhibited.
The "rock" is placed at the end of the pipe closest to the filter and the other end of the pipe is placed in the mouth. A flame from a match or cigarette lighter is then held under the rock. As the rock is heated, it melts, and the user inhales the gaseous smoke released during heating.
The effects are felt almost immediately after smoking, are very intense, and do not last long — usually five to ten minutes.
A heavily used crack–pipe tends to break at the ends as the user "pushes" the pipe. "Pushing" is a technique used to partially recover crack which hardens on the inside wall of the pipe as the pipe cools. The user pushes the filter through the pipe from one end to the other to collect the build-up inside the pipe. The ends of the pipe can be broken by the object used to push the filter, frequently a small screwdriver or stiff piece of wire. The user will usually attempt to remove the most jagged edges and continue using the pipe until it is too short to handle.
The tell–tale signs of a used crack pipe are a burned filter, jagged edges, and burn marks at one or both ends.
When smoked, cocaine is sometimes combined with other drugs, such as cannabis; this combination is known as "primo". Cocaine and heroin combined is known as "moonrock" and has caused many deaths, particularly in and around Los Angeles.
Cocaine is a potent blocker of the dopamine transporter (DAT) and a less potent blocker of the norepinephrine transporter (NET) and serotonin transporter (5HTT). Cocaine also blocks sodium channels, thereby interfering with the propagation of action potentials; thus, like lidocaine and novocaine, it acts as a local anesthetic. The locomotor enhancing properties of cocaine may be attributable to its blocking of dopaminergic transmission from the substantia nigra.
After cocaine is introduced to the body it travels to reward areas of the brain: the ventral tegmental area (VTA), the nucleus accumbens and the prefrontal cortex. These areas are saturated with dopamine synapses. Normally, after dopamine is released in the synaptic cleft, it binds to the dopamine receptors; reuptake sites (protein transported structures) will utilize the rest of the neurotransmitter (dopamine). In the presence of cocaine the normal process of reuptaking is breached. Cocaine binds to the uptake sites, which leaves a higher concentration of dopamine in the synaptic cleft. The higher activation of dopamine receptors in the post–synaptic cell causes increased production inside the cell. This will lead to changes including abnormal firing patterns.
Cocaine is almost completely metabolized, primarily in the liver, with only about 1% excreted unchanged in the urine. It is mostly eliminated as benzoylecgonine, the major metabolite of cocaine, and is also excreted in lesser amounts as ecgonine methyl ester and ecgonine.
Cocaine metabolites are detectable in urine for up to two days after cocaine is used. Benzoylecgonine can be detected in urine within four hours after cocaine inhalation and remains detectable in concentrations greater than 1000 ng/ml for as long as 48 hours.
Cocaine is a potent central nervous system stimulant. Its effects last from 20 minutes to several hours, dependant upon the dosage of cocaine taken and its purity.
The initial signs of stimulation are increased motor activity, restlessness, tachycardia, increased blood pressure, increased heart rate and euphoria. The euphoria is quickly followed by feelings of discomfort and depression and a craving to re-experience the drug. Potential side-effects include aggression and paranoia.
With excessive dosage the drug can produce hallucinations, paranoid delusions, itching, and formication.
Overdose causes tachy-arythmias and a marked elevation of blood pressure. These can be life threatening, especially if the user has existing cardiac problems.
Toxicity results in seizures, followed by respiratory and circulatory depression of medullar origin. This may lead to death from respiratory failure, stroke, cerebral hemorrhage, or heart-failure. Cocaine is also highly pyrogenic because the stimulation and increased muscular activity cause greater heat production. Heat loss is inhibited by the intense vasoconstriction. Cocaine–induced hyperthermia may cause muscle cell destruction and myoglobinuria resulting in renal failure. There is no specific antidote for cocaine overdose.
Cocaine use is associated with a lifetime risk of heart attack that is seven times that of non-users. During the hour after cocaine is used, heart attack risk rises twenty-four times. It accounts for 25% of the heart attacks in the 18–45 year-old age group.
Side effects from chronic smoking of cocaine include chest pain, lung trauma, shortness of breath, sore throat, hoarse voice, dyspnea, and an aching, flu-like syndrome. The smoking of cocaine also breaks down tooth enamel and causes tooth decay.
Chronic intranasal usage can degrade the cartilage separating the nostrils (the septum), leading eventually to its complete disappearance.
Cocaine is used as a topical anesthetic in eye and nasal surgery. The major disadvantage of this use cocaine's intense vasoconstrictor activity and potential for cardiovascular system toxicity. Although the vasoconstriction is sometimes an advantage as it reduces bleeding, cocaine has now been largely replaced in medicine by local anaesthetics that are simply combined with a vasoconstrictor such as phenylephrine or epinephrine.
Cocaine addiction is obsessive or uncontrollable abuse of cocaine. Twelve Step Cocaine Anonymous groups modeled on Alcoholics Anonymous exist to combat this problem.
Cocaine has positive reinforcement effects, which refers to the effect that certain stimuli have on behavior. That is, these effects include activation of the reinforcement mechanism. This activation strengthens the response that was just made. If the drug was taken by a fast acting route such as injection or inhalation, the response will be the act of taking more cocaine, so the response will be reinforced.
It is speculated that cocaine's addicting properties stem from its DAT-blocking effects (in particular, blocking the dopaminergic transmission from ventral tegmental area neurons). However, Ichiro Sora et al. published a paper in 1998 in the Proceedings of the National Academy of Sciences, showing that mice with no dopamine transporters still exhibited rewarding effects of cocaine administration. Sora's later work demonstrated that a combined DAT/5HTT knockout eliminated the rewarding effects.
A result of cocaine being in the reward section of the brain is that it produces higher frequencies of impulses which activate the reward system. Chronic use of cocaine creates a pathological pathway, which substitutes the natural reward function. In order to maintain this pathway, users must increase cocaine dosage (this phenomenon is called tolerance). Natural reinforcers such as food, water, or sex are no longer able to perform this function.
Besides the activation of the reward system, cocaine affects the metabolic activity of the brain. The brain of chronic cocaine users can not utilize glucose — the main energy source for the brain — which results in violation of many brain functions; it can also explain the craving for confectionery in cocaine users.
The National Household Survey on Drug Abuse (NHSDA) reported that, in 1999, cocaine was used by 3.7 million Americans, or 1.7 percent of the household population aged 12 and over. Estimates of the current number of those who use cocaine regularly (at least once per month) vary, but 1.5 million is a widely accepted figure within the research community.
Although cocaine use has not significantly changed over the last six years, the number of first-time users has increased 63 percent, from 574,000 in 1991, to 934,000 in 1998. While these numbers indicate that cocaine is still widely present in the United States, cocaine use is significantly less prevalent than it was during the early 1980s. Cocaine use peaked in 1982 when 10.4 million Americans (5.6 percent of the population) reportedly used cocaine.
The 1999 Monitoring the Future (MTF) survey found the proportion of American students reporting use of powder cocaine rose during the 1990s. In 1991, 2.3 percent of eighth-graders said they used cocaine in their lifetime. This figure rose to 4.7 percent in 1999. For the older grades, increases began in 1992 and continued through the beginning of 1999. Between those years, lifetime use of cocaine went from 3.3 percent to 7.7 percent among tenth-graders and from 6.1 percent to 9.8 percent among twelfth-graders. Lifetime use of crack cocaine, according to MTF, also increased among eighth, tenth, and twelfth graders, from an average of 2.0 percent in 1991 to 3.9 percent in 1999.
Perceived risk and disapproval of cocaine and crack use both decreased during the 1990s at all three grade levels. The 1999 NHSDA found the highest rate of monthly cocaine use was for those aged 18 to 25 at 1.7 percent, increasing from 1.2 percent in 1997. Rates declined between 1996 and 1998 for ages 26 to 34, while rates slightly increased for the 12 to 17 and 35 and older age groups. Studies also show people are experimenting with cocaine at younger and younger ages. NHSDA found a steady decline in the mean age of first use from 23.6 years in 1992 to 20.6 years in 1998.
Cocaine is readily available in all major U.S. metropolitan areas. According to the Summer 1998 Pulse Check, which is published by the Office of National Drug Control Policy, cocaine use has stabilized across the country, with a few increases reported in San Diego, Bridgeport, Miami, and Boston. In the West, cocaine use is down perhaps because some users are switching to methamphetamine, which is cheaper and provides a longer-lasting high.
In 1999, Colombia was the world's leading producer of cocaine. Three-quarters of the world's annual yield of cocaine was produced there, both from cocaine base imported from Peru and Bolivia and from locally grown coca. There was a 28 percent increase in the amount of potentially harvestable coca plants in Colombia in 1998. This, combined with crop reductions in Bolivia and Peru, made Colombia the nation with the largest area of coca under cultivation.
Cocaine shipments from South America transported through Mexico or Central America are generally moved over land or by air to staging sites in northern Mexico. The cocaine is then broken down into smaller loads for smuggling across the U.S.–Mexico border. The primary cocaine importation points in the United States are in Arizona, southern California, southern Florida, and Texas. Typically, land vehicles are driven across the Southwest Border.
Cocaine is also carried in small, concealed, kilogram quantities across the border by couriers known as "mules", who enter the United States either legally through ports of entry or illegally through undesignated points along the border. Colombian traffickers have also started using a new concealment method whereby they add chemical compounds to cocaine hydrochloride to produce "black cocaine." The cocaine in this substance is not detected by standard chemical tests or drug-sniffing canines.
Cocaine traffickers from Colombia, and recently Mexico, have also established a labyrinth of smuggling routes throughout the Caribbean, the Bahama Island chain, and South Florida. They often hire traffickers from Mexico or the Dominican Republic to transport the drug. The traffickers use a variety of smuggling techniques to transfer their drug to U.S. markets. These include airdrops of 500–700 kilograms in the Bahama Islands or off the coast of Puerto Rico, mid–ocean boat–to–boat transfers of 500–2,000 kilograms, and the commercial shipment of tonnes of cocaine through the port of Miami.
Bulk cargo ships are also used to smuggle cocaine to staging sites in the western Caribbean–Gulf of Mexico area. These vessels are typically 150 to 250 foot (50 to 80 m) coastal freighters that carry an average cocaine load of approximately 2.5 metric tonnes. Commercial fishing vessels are also used for smuggling operations. In areas with a high volume of recreational traffic, smugglers use the same types of vessels, such as go-fast boats, as those used by the local populations.
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