Cocaine
Un article de Vev.
Modèle:Pp-semi-protected Modèle:Otheruses
Cocaine is a crystalline tropane alkaloid that is obtained from the leaves of the coca plant. The name comes from "coca" in addition to the alkaloid suffix -ine, forming cocaine. It is both a stimulant of the central nervous system and an appetite suppressant. Specifically, it is a dopamine reuptake inhibitor. It gives a feeling to what has been described as a euphoric sense of happiness and increased energy. It is most often used recreationally for this effect. Because of the way it affects the mesolimbic reward pathway, cocaine is addictive. Nevertheless, cocaine is still used in medicine as a topical anesthetic, even in children, specifically in eye, nose and throat surgery.
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.
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History
Originally consumed without any processing, the chewing of coca leaves was popular among South American natives long before the arrival of the Spanish in the 16th century. The leaves were chewed in a manner consistent with modern use of coffee, chewed for a small burst of energy or stamina. The Spanish explorers noticed how the natives used the coca leaves and themselves partook in some cases, but the practice of chewing the raw leaves did not become especially popular among Europeans. Coca's turning point in Europe came in 1860 when Albert Niemann extracted pure cocaine powder from coca leaves. This refinement allowed the use of cocaine in many different medicinal products and beverages, most notably Coca-Cola and Vin Mariani.<ref>Ashley, Richard. Cocaine: Its History, Uses, and Effects New York: Warner Books, 1975.</ref> Freud began experimenting with cocaine around this time, consuming small quantities to combat depression, sharing his experience with other European physicians who also found cocaine to be an effective topical anesthetic. Freud became a fervent supporter of the use of cocaine as an anti-depressant, even publishing a manuscript detailing its virtues. Conan Doyle stood alone in the late 19th century depicting the destructive qualities of cocaine in his consulting detective, Sherlock Holmes.<ref> Modèle:Cite journal </ref> As cocaine's popularity increased, health risks were noted and seized upon by American legislators, who made the substance all but illegal in 1916.
Pharmacology
Appearance
Cocaine in its purest form is a white, pearly product. Cocaine appearing in powder form is a salt, typically cocaine hydrochloride (CAS 53-21-4). Street market cocaine is frequently adulterated or “cut” with various powdery fillers to increase its weight; the substances most commonly used in this process are baking soda; sugars, such as lactose, dextrose, inositol, and mannitol; and local anesthetics, such as lidocaine or benzocaine, which mimic or add to cocaine's numbing effect on mucous membranes. Cocaine may also be "cut" with other stimulants such as methamphetamine.<ref> Psychedelic Chemistry: Cocaine
. Retrieved on 2007-07-10.
</ref> Adulterated cocaine is often a white, off-white or pinkish powder.
The color of “crack” cocaine depends upon several factors including the origin of the cocaine used, the method of preparation – with ammonia or baking soda – and the presence of impurities, but will generally range from white to a yellowish cream to a light brown. Its texture will also depend on the adulterants, origin and processing of the powdered cocaine, and the method of converting the base. It ranges from a crumbly texture, sometimes extremely oily, to a hard, almost crystalline nature.
Forms of cocaine
Cocaine sulfate
Cocaine sulfate is produced by macerating coca leaves along with water that has been acidulated with sulfuric acid, or an aromatic-based solvent, like kerosene or benzene. This is often accomplished by placing the ingredients into a vat and stomping on them, in a manner similar to the traditional method for crushing grapes. A more popular method in modern times is to form a makeshift "vat" by spreading a heavy nylon tarp on the floor of an enclosed area and shred the leaves with a gas-powered weed-eater. This method is fast, and not only shreds the leaves, but results in bruising and fragmenting of the remaining pieces, aiding the extraction process. After the maceration is completed, the water is evaporated to yield a pasty mass of impure cocaine sulfate. The sulfate salt itself is an intermediate step to producing cocaine hydrochloride.
Freebase
As the name implies, “freebase” is the base form of cocaine, as opposed to the salt form of cocaine hydrochloride. Whereas cocaine hydrochloride is extremely soluble in water, cocaine base is insoluble in water and is therefore not suitable for drinking, snorting or injecting. Whereas cocaine hydrochloride is not well-suited for smoking because the temperature at which it vaporizes is very high and close to the temperature at which it burns, cocaine base vaporizes at a much lower temperature, which makes it suitable for inhalation.
Smoking freebase is preferred by many users[citation needed] because the cocaine is absorbed immediately into blood via the lungs, reaching the brain in about five seconds. The rush is much more intense than snorting the same amount of cocaine nasally, but the effects do not last as long. The peak of the freebase rush is over almost as soon as the user exhales the vapor, but the high typically lasts 5–10 minutes afterward. What makes freebasing particularly dangerous is that users typically do not wait that long for their next hit and will continue to smoke freebase until none is left. These effects are similar to those that can be achieved by injecting or “slamming” cocaine hydrochloride, but without the risks associated with intravenous drug use (though there are other serious risks associated with smoking freebase).
Freebase cocaine is produced by first dissolving cocaine hydrochloride in water. Once dissolved in water, cocaine hydrochloride (Coc HCl) dissociates into protonated cocaine ion (Coc-H+) and chloride ion (Cl– ). Any solids that remain in the solution are not cocaine (they are part of the cut) and are removed by filtering. A base, typically ammonia (NH3), is added to the solution. The following net chemical reaction takes place:
As freebase cocaine (Coc) is insoluble in water, it precipitates and the solution becomes cloudy. To recover the freebase in the "traditional" manner, diethyl ether is added to the solution. Since freebase is highly soluble in ether, a vigorous shaking of the mixture results in the freebase being dissolved in the ether. As ether is practically insoluble in water, it can be siphoned off. The ether is then left to evaporate, leaving behind the nearly pure freebase.
Handling diethyl ether is dangerous because ether is extremely flammable, its vapors are heavier than air and can "creep" from an open bottle, and in the presence of oxygen it can form peroxides, which can spontaneously combust. Demonstrative of the dangers of the practice, comedian Richard Pryor used to perform a skit in which he poked fun at himself over a 1980 incident in which he caused an explosion and ignited himself attempting to smoke "freebase", presumably while still wet with ether (though his ex wife Jennifer Lee Pryor said that he poured high-proof rum over his body and torched himself in a drug psychosis).
Crack cocaine
Due to the dangers of using ether to produce pure freebase cocaine, cocaine producers began to omit the step of removing the freebase cocaine precipitate from the ammonia mixture. Typically, filtration processes are also omitted. The end result of this process is that the cut, in addition to the ammonium salt (NH4Cl), remains in the freebase cocaine after the mixture is evaporated. The “rock” that is thus formed also contains a small amount of water. Sodium bicarbonate (baking soda) is also preferred in preparing the freebase, for when commonly "cooked" the ratio is 50/50 to 40/60% cocaine/bicarbonate. This acts as a filler which extends the overall profitability of illicit sales. Crack cocaine may be reprocessed in small quantities with water (users refer to the resultant product as "cookback"). This removes the residual bicarbonate, and any adulterants or cuts that have been used in the previous handling of the cocaine and leaves a relatively pure, anhydrous cocaine base.
When the rock is heated, this water boils, making a crackling sound (hence the onomatopoetic “crack”). Baking soda is now most often used as a base rather than ammonia for reasons of lowered stench and toxicity; however, any weak base can be used to make crack cocaine. Strong bases, such as sodium hydroxide, tend to hydrolyze some of the cocaine into non-psychoactive ecgonine.
Chewed/eaten
Coca leaves are typically mixed with an alkaline substance (such as lime) and chewed into a wad that is retained in the mouth between gum and cheek (much in the same as chewing tobacco is chewed) and sucked of its juices. The juices are absorbed slowly by the mucous membrane of the inner cheek and by the gastrointestinal tract when swallowed. Alternatively, coca leaves can be infused in liquid and consumed like tea. Ingesting coca leaves generally is an inefficient means of administering cocaine. Advocates of the consumption of the coca leaf state that coca leaf consumption should not be criminalized as it is not actual cocaine, and consequently it is not properly the illicit drug. Because cocaine is hydrolyzed and rendered inactive in the acidic stomach, it is not readily absorbed when ingested alone. Only when mixed with a highly alkaline substance (such as lime) can it be absorbed into the bloodstream through the stomach. The efficiency of absorption of orally administered cocaine is limited by two additional factors. First, the drug is partly catabolized by the liver. Second, capillaries in the mouth and esophagus constrict after contact with the drug, reducing the surface area over which the drug can be absorbed. Nevertheless, cocaine metabolites can be detected in the urine of subjects that have sipped even one cup of coca leaf infusion. Therefore, this is an actual additional form of administration of cocaine, albeit an inefficient one.
Orally administered cocaine takes approximately 30 minutes to enter the bloodstream. Typically, only a third of an oral dose is absorbed, although absorption has been shown to reach 60% in controlled settings. Given the slow rate of absorption, maximum physiological and psychotropic effects are attained approximately 60 minutes after cocaine is administered by ingestion. While the onset of these effects is slow, the effects are sustained for approximately 60 minutes after their peak is attained.
Contrary to popular belief, both ingestion and insufflation result in approximately the same proportion of the drug being absorbed: 30 to 60%. Compared to ingestion, the faster absorption of insufflated cocaine results in quicker attainment of maximum drug effects. Snorting cocaine produces maximum physiological effects within 40 minutes and maximum psychotropic effects within 20 minutes, however, a more realistic activation period is closer to 5 to 10 minutes, which is similar to ingestion of cocaine. Physiological and psychotropic effects from nasally insufflated cocaine are sustained for approximately 40 - 60 minutes after the peak effects are attained.<ref>G. Barnett, R. Hawks and R. Resnick, "Cocaine Pharmacokinetics in Humans," 3 Journal of Ethnopharmacology 353 (1981); Jones, supra note 19; Wilkinson et al., Van Dyke et al.</ref>
Mate de coca or coca-leaf infusion is also a traditional method of consumption and is often recommended in coca producing countries, like Peru and Bolivia, to ameliorate some symptoms of altitude sickness. This method of consumption has been practiced for many centuries by the native tribes of South America. One specific purpose of ancient coca leaf consumption was to increase energy and reduce fatigue in messengers who made multi-day quests to other settlements.
In 1986 an article in the Journal of the American Medical Association revealed that U.S. health food stores were selling dried coca leaves to be prepared as an infusion as “Health Inca Tea.”<ref>Modèle:Cite journal</ref> While the packaging claimed it had been “decocainized,” no such process had actually taken place. The article stated that drinking two cups of the tea per day gave a mild stimulation, increased heart rate, and mood elevation, and the tea was essentially harmless. Despite this, the DEA seized several shipments in Hawaii, Chicago, Illinois, Georgia, and several locations on the East Coast of the United States, and the product was removed from the shelves. Nevertheless, today coca leaf teabags (named "mate de coca") illegally smuggled into the U.S. can be readily purchased online via Internet stores and even eBay.
Insufflation
Insufflation (known colloquially as "snorting," "sniffing," or "blowing") is the most common method of ingestion of recreational powdered cocaine in the Western world. Cocaine is not inhaled using this method. The drug coats and is absorbed through the mucous membranes lining the sinuses. When insufflating cocaine, absorption through the nasal membranes is approximately 30-60%, with higher doses leading to increased absorption efficiency. Any material not directly absorbed through the mucous membranes is collected in mucus and swallowed (this "drip" is considered pleasant by some and unpleasant by others). In a study<ref name="Volkow">Modèle:Cite journal</ref> of cocaine users, the average time taken to reach peak subjective effects was 14.6 minutes. Any damage to the inside of the nose is because cocaine highly constricts blood vessels – and therefore blood and oxygen/nutrient flow – to that area.
Prior to insufflation, cocaine powder must be divided into very fine particles. Cocaine of high purity breaks into fine dust very easily, except when it is moist (not well stored) and forms "chunks," which reduces the efficiency of nasal absorption.
Rolled up banknotes, hollowed-out pens, cut straws, pointed ends of keys, specialized spoons, long fingernails, and (clean) tampon applicators are often used to insufflate cocaine. Such devices are often called "tooters" by users. The cocaine typically is poured onto a flat, hard surface (such as a mirror) and divided into "bumps", "lines" or "rails", and then insufflated.<ref>cesar.umd.edu - Cocaine terminology</ref> The amount of cocaine in a line varies widely from person to person and occasion to occasion (the purity of the cocaine is also a factor), but one line is generally considered to be a single dose and is typically 35 mg (a "bump") to 100 mg (a "rail").[citation needed] As tolerance builds rapidly in the short-term (hours), many lines are often snorted to produce greater effects.
A study by Bonkovsky and Mehta published in Am Acad Dermatol (2001 Feb;44(2):159-82) reported that, just like shared needles, the sharing of straws used to "snort" cocaine can spread blood diseases such as Hepatitis C.<ref>www.erowid.org - Cocaine, Bits & Pieces</ref>
Injected
Drug injection provides the highest blood levels of drug in the shortest amount of time. Upon injection, cocaine reaches the brain in a matter of seconds, and the exhilarating rush that follows can be so intense that it induces some users to vomit uncontrollably which causes bleeding of the esophagus.[citation needed] In a study<ref name="Volkow" /> of cocaine users, the average time taken to reach peak subjective effects was 3.1 minutes. The euphoria passes quickly. Aside from the toxic effects of cocaine, there is also danger of circulatory emboli from the insoluble substances that may be used to cut the drug. As with all injected illicit substances, there is a risk of the user contractive blood borne infections if sterile injecting equiptment is not available or used.
An injected mixture of cocaine and heroin, known as “speedball” or “moonrock”, is a particularly popular and dangerous combination, as the converse effects of the drugs actually complement each other, but may also mask the symptoms of an overdose. It has been responsible for numerous deaths, particularly in and around Los Angeles, including celebrities such as John Belushi, Chris Farley (in Chicago), Mitch Hedberg (in North NJ) River Phoenix and Layne Staley (in Seattle).
Experimentally, cocaine injections can be delivered to animals such as fruit flies to study the mechanisms of cocaine addiction.<ref>Modèle:Cite journal</ref>
Smoked
- See also: Crack cocaine above.
Modèle:Original research Smoking freebase or crack cocaine is most often accomplished using a pipe made from a small glass tube about one quarter-inch (about 6 mm) in diameter and on the average, four inches long. These are sometimes called "stems", "horns", "blasters" and "straight shooters," readily available in convenience stores or smoke shops. They will sometimes contain a small paper flower and are promoted as a romantic gift. Buyers usually ask for a "rose" or a "flower." An alternate method is to use a small length of a radio antenna or similar metal tube. To avoid burning the user's fingers and lips on the metal pipe, a small piece of paper or cardboard (such as a piece torn from a matchbook cover) is wrapped around one end of the pipe and held in place with either a rubber band or a piece of adhesive tape. A popular (usually pejorative) term for crack pipes is "glass dick." Tire pressure gauges have also been used by breaking off their tops and removing their numbered sticks. These can be purchased at most convenience stores or gas stations.
A small piece (approximately one inch) of clean heavy copper or occasionally stainless steel scouring pad—often called a "brillo" or "chore", from the scouring pads of the same name—is placed into one end of the tube and carefully packed down to approximately three-quarters of an inch. Prior to insertion, the "brillo" is burnt off to remove any oily coatings that may be present. It then serves as a reduction base and flow modulator in which the "rock" can be melted and boiled to vapor.
Another method is to use a deep socket, typically 12 mm, wrapped with electrical tape. Instead of Chore Boy, users typically employ high grade (very fine) speaker wire rolled into a ball as the filter medium. A Zippo lighter is often used because of its stronger flame,[citation needed] but the taste of naphtha is quite noticeable. However, the socket is practically indestructible and inconspicuous.
A less sophisticated but common method is to use a discarded soda can and puncture several small holes on the side of the can near its bottom. Tobacco ash is then placed in the divot created with the drug placed on top. The mouthpiece is the original opening of the can, creating a cost-effective alternative to a proper crack pipe.
To smoke the "rock," it is placed at the end of the pipe, closest to the filter. The other end is then placed in the user's mouth and a flame from a cigarette lighter or hand-held torch is held under the "rock." As the "rock" is heated, it melts and heats into vapor, which the user inhales as smoke.
The effects, felt almost immediately after smoking, are very intense and do not last long — usually five to fifteen minutes. In a study<ref name="Volkow" /> performed on crack cocaine users, the average time taken for them to reach their peak subjective "high" was 1.4 minutes. Most (especially frequent) users crave more immediately after the peak. "Crack houses" depend on these cravings by providing a place for smoking crack to its users, and a ready supply of small bags for sale.
A heavily-used crack pipe tends to fracture at its end due to overheating from the flame used to heat the crack, typically because users attempt to inhale every last bit of the drug on the metal wool filter. The end is often broken further as users "push" the pipe. "Pushing" is a technique used to partially recover crack that hardens on the inside wall of the pipe as the pipe cools. This is accomplished by pushing the metal wool filter through the pipe from one end to the other in order to collect the build-up inside the pipe, which is a very pure and potent form of the base. 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. Users will often remove the most jagged edges and continue using the pipe until it becomes so short that it burns their lips and fingers. To continue using the pipe, users will sometimes wrap a small piece of paper or cardboard around its one end and hold it in place with a rubber band or adhesive tape. Of course, not all crack cocaine users will allow it to get that short, and will instead opt for a new or different pipe. The telltale signs of a used crack pipe are a glass tube with burn marks at one or both ends and a clump of metal wool inside. The language referring to paraphernalia and practices of smoking cocaine vary across the United States, as do the packaging methods in the street level sale.
When smoked, cocaine is sometimes combined with other drugs, such as cannabis; often rolled into a joint or blunt. This combination is known as "primo","hype", "jay bomb", "shake and bake", a "turbo", a "yolabowla", "SnowCaps", "Canadian Health Care", "B-51er", a "cocoapuff", a "dirty", a "woo", or "geeking." Crack smokers who are being drug tested may also make their "primo" with cigarette tobacco instead of cannabis, since a crack smoker can test clean within two to three days of use, if only urine (and not hair) is being tested.
Powdered cocaine is sometimes smoked, but it is inefficient as the heat involved destroys much of the chemical. One way of smoking powder is to put a "bump" into the end of an unlit cigarette, smoking it in one go as the user lights the cigarette normally. This cigarette is then referred to as a "Coolie". Alternatively, cocaine powder may be sprinkled onto the marijuana in a blunt or possibly a joint and then smoked. This is known as a "Chewy" or may also be referred to by one of the names mentioned above for crack-laced marijuana. When a marijuana bowl is laced with cocaine powder, it is often referred to as a "SnowCap" which is a reference to snow capped mountains."
Coca leaf infusions
Coca herbal infusion (also referred to as Coca tea) is used in coca-leaf producing countries much as any herbal medicinal infusion would elsewhere in the world. The free and legal commercialization of dried coca leaves under the form of filtration bags to be used as "coca tea" has been actively promoted by the governments of Peru and Bolivia for many years as a drink having medicinal powers. Visitors to the city of Cuzco in Peru, and La Paz in Bolivia are greeted with the offering of coca leaf infusions (prepared in tea pots with whole coca leaves) purportedly to help the newly-arrived traveler overcome the malaise of high altitude sickness. The effects of drinking coca tea are a mild stimulation and mood lift. It does not produce any significant numbing of the mouth nor does it give a rush like snorting cocaine. In order to prevent the demonization of this product, its promoters publicize the unproven concept that much of the effect of the ingestion of coca leaf infusion would come from the secondary alkaloids, as being not only quantitatively different from pure cocaine but also qualitatively different.
It has been promoted as an adjuvant for the treatment of cocaine dependence. In one controversial study, coca leaf infusion was used -in addition to counseling- to treat 23 addicted coca-paste smokers in Lima, Peru. Relapses fell from an average of four times per month before treatment with coca tea to one during the treatment. The duration of abstinence increased from an average of 32 days prior to treatment to 217 days during treatment. These results suggest that the administration of coca leaf infusion plus counseling would be an effective method for preventing relapse during treatment for cocaine addiction.<ref>Modèle:Cite journal</ref> Importantly, these results also suggest strongly that the primary pharmacologically active metabolite in coca leaf infusions is actually cocaine and not the secondary alkaloids.
The cocaine metabolite benzoylecgonine can be detected in the urine of people a few hours after drinking one cup of coca leaf infusion.
Oral
Cocaine has been used medically and informally as an oral anesthetic. Many users rub the powder along the gum line, or onto a cigarette filter which is then smoked, which numbs the gums and teeth - hence the colloquial names of "numbies", "gummies" or "cocoa puffs" for this type of administration. This is mostly done with the small amounts of cocaine remaining on a surface after insufflation. Another oral method is to wrap up some cocaine in rolling paper and swallow it. This is sometimes called a "snow bomb."
Physical mechanisms
The pharmacodynamics of cocaine involve the complex relationships of neurotransmitters (inhibiting monoamine uptake in rats with ratios of about: Serotonin:Dopamine = 2:3, Serotonin:Norepinephrine = 2:5<ref>Rothman, et al. "Amphetamine-Type Central Nervous System Stimulants Release Norepinepehrine more Potently than they Release Dopamine and Serotonin." (2001): Synapse 39, 32-41 (Table V. on page 37)</ref>) The most extensively studied effect of cocaine on the central nervous system is the blockage of the dopamine transporter protein. Dopamine transmitter released during neural signaling is normally recycled via the transporter; i.e., the transporter binds the transmitter and pumps it out of the synaptic cleft back into the pre-synaptic neuron, where it is taken up into storage vesicles. Cocaine binds tightly at the dopamine transporter forming a complex that blocks the transporter's function. The dopamine transporter can no longer perform its reuptake function, and thus dopamine accumulates in the extracellular space (synaptic cleft). This results in an enhanced and prolonged post-synaptic effect of dopaminergic signalling at dopamine receptors on the receiving neuron. Prolonged exposure to cocaine, as occurs with habitual use, leads to homeostatic dysregulation of normal (i.e. without cocaine) dopaminergic signaling via downregulation of dopamine receptors and enhanced signal transduction. The decreased dopaminergic signalling after chronic cocaine use may contribute to depressive mood disorders and sensitize this important brain reward circuit to the reinforcing effects of cocaine (e.g. enhanced dopaminergic signalling only when cocaine is self-administered). This sensitization contributes to the intractable nature of addiction and relapse.
Dopamine-rich brain regions such as the ventral tegmental area, nucleus accumbens, and prefrontal cortex are frequent targets of cocaine addiction research. Of particular interest is the pathway consisting of dopaminergic neurons originating in the ventral tegmental area that terminate in the nucleus accumbens. This projection may function as a "reward center", in that it seems to show activation is response to drugs of abuse like cocaine in addition to natural rewards like food or sex.<ref name="pmid10529820">Modèle:Cite journal</ref> While the precise role of dopamine in the subjective experience of reward is highly controversial among neuroscientists, the release of dopamine in the nucleus accumbens is widely considered to be at least partially responsible for cocaine's rewarding effects. This hypothesis is largely based on laboratory data involving rats that are trained to self-administer cocaine. If dopamine antagonists are infused directly into the nucleus accumbens, well-trained rats self-administering cocaine will undergo extinction (i.e. initially increase responding only to stop completely) thereby indicating that cocaine is no longer reinforcing (i.e. rewarding) the drug-seeking behavior.
Cocaine also blocks sodium channels, thereby interfering with the propagation of action potentials; thus, like lignocaine and novocaine, it acts as a local anesthetic. Cocaine also causes vasoconstriction, thus reducing bleeding during minor surgical procedures. The locomotor enhancing properties of cocaine may be attributable to its enhancement of dopaminergic transmission from the substantia nigra. Recent research points to an important role of circadian mechanisms<ref>Modèle:Cite journal</ref> and clock genes<ref>Modèle:Cite journal</ref> in behavioral actions of cocaine.
Because nicotine increases the levels of dopamine in the brain, many cocaine users find that consumption of tobacco products during cocaine use enhances the euphoria. This, however, may have undesirable consequences, such as uncontrollable chain smoking during cocaine use (even users who do not normally smoke cigarettes have been known to chain smoke when using cocaine), in addition to the detrimental health effects and the additional strain on the cardiovascular system caused by tobacco.
In addition to irritability, mood disturbances, restlessness, paranoia, and auditory hallucinations, crack can cause several dangerous physical conditions. It can lead to disturbances in heart rhythm and heart attacks, as well as chest pains or even respiratory failure. In addition, strokes, seizures and headaches are common in heavy users.
Cocaine can often cause reduced food intake, many chronic users lose their appetite and can experience severe malnourishment and significant weight loss.
Metabolism and excretion
Cocaine is extensively metabolized, primarily in the liver, with only about 1% excreted unchanged in the urine. The metabolism is dominated by hydrolytic ester cleavage, so the eliminated metabolites consist mostly of benzoylecgonine, the major metabolite, and in lesser amounts ecgonine methyl ester and ecgonine.
If taken with alcohol, cocaine combines with the ethanol in the liver to form cocaethylene, which is both more euphorigenic and has higher cardiovascular toxicity than cocaine by itself[citation needed]. It is precisely this characteristic that has prompted heavily inebriated persons, since the early 20th century, to snort cocaine to relieve them of the depressive effects of alcohol abuse.
Depending on liver and kidney function, cocaine metabolites are detectable in urine. Benzoylecgonine can be detected in urine within four hours after cocaine intake and remains detectable in concentrations greater than 150 ng/ml typically for up to eight days after cocaine is used. Detection of accumulation of cocaine metabolites in hair is possible in regular users until the sections of hair grown during use are cut or fall out.
Effects and health issues
Acute
Cocaine is a potent central nervous system stimulant. Its effects can last from 20 minutes to several hours, depending upon the dosage of cocaine taken, purity, and method of administration.
The initial signs of stimulation are hyperactivity, restlessness, increased blood pressure, increased heart rate and euphoria. The euphoria is sometimes followed by feelings of discomfort and depression and a craving to experience the drug again. Sexual interest and pleasure can be amplified. Side effects can include twitching, paranoia, and impotence, which usually increases with frequent usage.
With excessive dosage the drug can produce itching, tachycardia, hallucinations, and paranoid delusions. Overdoses cause tachyarrhythmias and a marked elevation of blood pressure. These can be life-threatening, especially if the user has existing cardiac problems.
The LD50 of cocaine when administered to mice is 95.1 mg/kg.<ref>Modèle:Cite journal</ref> 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. Emergency treatment often consists of administering a benzodiazepine sedation agent, such as diazepam (Valium) to decrease the elevated heart rate and blood pressure. Physical cooling (ice, cold blankets, etc...) and acetaminophen may be used to treat hyperthermia, while specific treatments are then developed for any further complications.<ref> Cocaine Overdose
.</ref> However, there is no specific antidote for cocaine overdose.
In cases where a patient is unable or unwilling to seek medical attention, cocaine overdoses resulting in mild-moderate tachycardia (i.e.: a resting pulse greater than 120 bpm), may be initially treated with 20 mg of orally administered diazepam or equivalent benzodiazepine (eg: 2mg lorazepam). Acetaminophen and physical cooling may likewise be used to reduce mild hyperthermia (<39 C). However, a history of high blood pressure or cardiac problems puts the patient at high risk of cardiac arrest or stroke, and requires immediate medical treatment. Similarly, if benzodiazepine sedation fails to reduce heart rate or body temperatures fails to lower, professional intervention is necessary. <ref> Management of Poisoning and Drug Overdose: Specific Drugs and Poisons
.</ref> <ref> Clinical predictors of leak after laparoscopic Roux-en-Y gastric bypass for morbid obesity.
.</ref> <ref> Cocaine Drug Use and Dependence: Merck Manual Professional.
.</ref>
Cocaine's primary acute effect on brain chemistry is to raise the amount of dopamine and serotonin in the nucleus accumbens (the pleasure center in the brain); this effect ceases, due to metabolism of cocaine to inactive compounds and particularly due to the depletion of the transmitter resources (tachyphylaxis). This can be experienced acutely as feelings of depression, as a "crash" after the initial high. Further mechanisms occur in chronic cocaine use.
Studies have shown that cocaine usage during pregnancy triggers premature labor<ref> Modèle:Cite journal</ref> and may lead to abruptio placentae.<ref> Modèle:Cite journal</ref>
Cocaine can cause coronary artery spasms which lead to a myocardial infarction. This effect can happen randomly to any user. The coronary artery spasms can occur on the users first usage or any other usage after. The coronary spasms cause the ectopic ventricular foci of the heart to become hypoxic and the extreme irritability can trigger life-threatening ventricular arrhythmias.
Chronic
Chronic cocaine intake causes brain cells to adapt functionally to strong imbalances of transmitter levels in order to compensate extremes. Thus, receptors disappear from the cell surface or reappear on it, resulting more or less in an "off" or "working mode" respectively, or they change their susceptibility for binding partners (ligands)—mechanisms called down-/upregulation. Chronic cocaine use leads to a DATS upregulation,Modèle:Verify source further contributing to depressed mood states. Physical withdrawal is not dangerous, and is in fact restorative. The experience of insatiable hunger, aches, insomnia/oversleeping, lethargy, and persistent runny nose are often described as very unpleasant. Depression with suicidal ideation may develop in very heavy users. Finally, a loss of vesicular monoamine transporters, neurofilament proteins, and other morphological changes appear to indicate a long term damage of dopamine neurons.
All these effects contribute a rise in tolerance thus requiring a larger dosage to achieve the same effect. The lack of normal amounts of serotonin and dopamine in the brain is the cause of the dysphoria and depression felt after the initial high. The diagnostic criteria for cocaine withdrawal is characterized by a dysphoric mood, fatigue, unpleasant dreams, insomnia or hypersomnia, E.D., increased appetite, psychomotor retardation or agitation, and anxiety.
Cocaine abuse also has multiple physical health consequences. It is associated with a lifetime risk of heart attack that is 6% higher than that of non-users. During the hour after cocaine is used, heart attack risk rises 24-fold.<ref>Modèle:Cite journal</ref>
Side effects from chronic smoking of cocaine include hemoptysis, bronchospasm, pruritus, fever, diffuse alveolar infiltrates without effusions, pulmonary and systemic eosinophiliachest, pain, lung trauma, shortness of breath, sore throat, asthma, hoarse voice, dyspnea, and an aching, flu-like syndrome. A common but untrue belief is that the smoking of cocaine chemically breaks down tooth enamel and causes tooth decay. However, cocaine does often cause involuntary tooth grinding, known as bruxism, which can deteriorate tooth enamel and lead to gingivitis.<ref>Modèle:Cite journal</ref>
Chronic intranasal usage can degrade the cartilage separating the nostrils (the septum nasi), leading eventually to its complete disappearance. Due to the absorption of the cocaine from cocaine hydrochloride, the remaining hydrochloride forms a dilute hydrochloric acid.<ref name="pagliaros"/>
Cocaine may also greatly increase this risk of developing rare autoimmune or connective tissue diseases such as lupus, Goodpasture's disease, vasculitis, glomerulonephritis, Stevens-Johnson syndrome and other diseases.<ref> scienceblog.com
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</ref><ref>Modèle:Cite journal</ref><ref> karger.com
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</ref><ref> jnnp.bmjjournals.com
. Retrieved on 2007-07-10.
</ref> It can also cause a wide array of kidney diseases and renal failure.<ref> cjasn.asnjournals.org
. Retrieved on 2007-07-10.
</ref><ref> ndt.oxfordjournals.org
. Retrieved on 2007-07-10.
</ref> While these conditions are normally found in chronic use they can also be caused by short term exposure in susceptible individuals.
Cocaine abuse doubles both the risks of hemorrhagic and ischemic strokes.<ref> MedlinePlus: Stroke a risk for cocaine, amphetamine abusers
. Retrieved on 2007-07-10.
</ref>
Years after the abuse has ended, many ex-abusers report a noticeably reduced attention span.
Cocaine as a local anesthetic
Cocaine was historically useful as a topical anesthetic in eye and nasal surgery, although it is now predominantly used for nasal and lacrimal duct surgery. The major disadvantages of this use are cocaine's intense vasoconstrictor activity and potential for cardiovascular toxicity. Cocaine has since been largely replaced in Western medicine by synthetic local anaesthetics such as benzocaine, proparacaine, and tetracaine though it remains available for use if specified. If vasoconstriction is desired for a procedure (as it reduces bleeding), the anesthetic is combined with a vasoconstrictor such as phenylephrine or epinephrine. In Australia it is currently prescribed for use as a local anesthetic for conditions such as mouth and lung ulcers. Some ENT specialists occasionally use cocaine within the practice when performing procedures such as nasal cauterization. In this scenario dissolved cocaine is soaked into a ball of cotton wool, which is placed in the nostril for the 10-15 minutes immediately prior to the procedure, thus performing the dual role of both numbing the area to be cauterized and also vasoconstriction. Even when used this way, some of the used cocaine may be absorbed through oral or nasal mucosa and give systemic effects.
Prohibition currently
The production, distribution and sale of cocaine products is restricted (and illegal in most contexts) in most countries as regulated by the Single Convention on Narcotic Drugs, and the United Nations Convention Against Illicit Traffic in Narcotic Drugs and Psychotropic Substances. In the United States the manufacture, importation, possession, and distribution of cocaine is additionally regulated by the 1970 Controlled Substances Act.
Some countries, such as Peru and Bolivia permit the cultivation of coca leaf for traditional consumption by the local indigenous population, but nevertheless prohibit the production, sale and consumption of cocaine.
Some parts of Europe and Australia allow processed cocaine for medicinal uses only.
In certain countries in the Middle East and Asia, such as Singapore, Saudi Arabia and Indonesia, being in possession of cocaine can be punishable by death.[citation needed]
Interdiction
In 2004, according to the United Nations, 589 metric tons of cocaine were seized globally by law enforcement authorities. Colombia seized 188 tons, the United States 166 tons, Europe 79 tons, Peru 14 tons, Bolivia 9 tons, and the rest of the world 133 tons.<ref> [1]</ref>
Illicit trade
Because of the extensive processing it undergoes during preparation, cocaine is generally treated as a 'hard drug', with severe penalties for possession and trafficking. Demand remains high, and consequently black market cocaine is quite expensive. Unprocessed cocaine, such as coca leaves, are occasionally purchased and sold, but this is exceedingly rare as it is much easier and more profitable to conceal and smuggle it in powdered form. The scale of the market is immense: 770 tonnes times $100 per gram retail = up to $77 billion.
Production
By 1999, Colombia had become 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 (primarily the Huallaga Valley) and Bolivia, and from locally grown coca. There was a 28% increase from the amount of potentially harvestable coca plants which were grown 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 after the mid-1990s. Coca grown for traditional purposes by indigenous communities, a use which is still present and is permitted by Colombian laws, only makes up a small fragment of total coca production, most of which is used for the illegal drug trade. Attempts to eradicate coca fields through the use of defoliants have devastated part of the farming economy in some coca growing regions of Colombia, and strains appear to have been developed that are more resistant or immune to their use. Whether these strains are natural mutations or the product of human tampering is unclear. These strains have also shown to be more potent than those previously grown, increasing profits for the drug cartels responsible for the exporting of cocaine. The cultivation of coca has become an attractive, and in some cases even necessary, economic decision on the part of many growers due to the combination of several factors, including the persistence of worldwide demand, the lack of other employment alternatives, the lower profitability of alternative crops in official crop substitution programs, the eradication-related damages to non-drug farms, and the spread of new strains of the coca plant.
| 2000 | 2001 | 2002 | 2003 | 2004 | |
|---|---|---|---|---|---|
| Net Cultivation (km²) | 1875 | 2218 | 2007.5 | 1663 | 1662 |
| Potential Pure Cocaine Production (tonnes) | 770 | 925 | 830 | 680 | 645 |
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