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Cocaine
A white powder purified from the leaves of the Erythroxylon coca plant native to the Andes Mountains; especially in Peru.
Cocaine has been used for probably thousands of years while the first written of cocaine use was written by Amerigo Vespucci in 1499 about the early South American civilizations.
Early use was by chewing the leaves of the plant and even today many of the natives in the mountain regions use the leaf on a daily (continuous) basis without significant social problems.
The drug cocaine was purified around 1860 by the French chemist Angelo Mariani and it subsequently was added to a variety of products including the one which introduced cocaine to the general population in Europe (and beyond): Vin Mariani.
Products containing cocaine were widely used throughout western civilizations because it clearly “freed the body from fatigue, lifted the spirits, and caused a sense of well-being”.
The Pope even gave Mariani a medal for his contributions to society and the use of cocaine was endorsed by many physicians and national leaders before the turn of the century (Czar/Czarina of Russia, Prince of Wales, Kings of Norway, Sweden, and even President McKinley of the USA).
With the passage of the Harrison Act in 1914, the free use of cocaine-containing products disappeared because cocaine was mistakenly classified as a narcotic.
Recognition of the addicting and psychotic properties of cocaine by medical personnel in the late 1880’s led to diminished use in medicine.
Effects of cocaine are dependent on dose and route of administration:
The medical use of cocaine was originally as a treatment for morphine addiction and as a local anesthetic.
The need for increasing doses with continuing use to prevent symptoms of narcotic withdrawal led to the production of paranoid psychosis in patients. With high enough doses, everyone will experience paranoid psychotic (& violent) episodes.
Cocaine also is a good local anesthetic providing local numbness as well as local vasoconstriction – ideal for oral surgery. The development of derivatives which have the same anesthetic effects of cocaine without the CNS stimulation (such as Novocaine in 1906) replaced the medical use of cocaine.
Oralusually chewing leaves (or as part of the many patent medicines and potions) resulting in a dose of approximately 20 to 400 mg
slow onset of action
mild & sustained CNS stimulation
least likely to cause addiction
Inhaling
Snorting powder into the nose resulting in an approximate 100 mg dose into blood
Substantial CNS stimulation within minutes& lasts 30 – 40 minutes
A rebound depression/dysphoria results within minutes of the end of the “high”
Low likelihood of causing addiction
Intravenous Administration
Large (hundreds of mg) amounts of cocaine can be injected
Intense CNS stimulation within seconds and lasts 10 to 20 minutes
Intense depression and dysphoria; often re-inject immediately – paranoia/psychosis likely at high doses
Highly addicting
Smoking
Most often through use of a water pipe
Cocaine must first be “freebased” - dissolve the cocaine in a base and then extract cocaine with a (highly flammable) solvent and smoke the resulting pure cocaine
More intense CNS stimulation than IV route
More intense depression/dysphoria than IV route – paranoia/psychosis likely
Highly addicting (even more than IV use)
Crack
Available since 1985/1986; cheaper than cocaine and can be smoked without use of solvents.
Made by mixing cocaine with baking soda, removing both impurities and the HCl
Dried paste is ~90% pure cocaine and is smoked
Often considered a better “high” than smoking freebased cocaine or IV administered cocaine
Most intense depression/dysphoria – paranoia/psychosis likely
Highly addicting (MOST?)
12
10
8
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1975 1980 1985 1990 1995 2000
Cocaine Use By High School Seniors
Total Cocaine
Crack
Cocaine abuse statistics are somewhat different than for other drugs of abuse:
Of approximately 3 – 4 million (USA – 1998) regular users about 650,000 are heavy abusers, about a 20% incidence (2x the “normal” incidence of compulsive abuse with most other drugs). Of these abusers, the majority smoke the drug and usually progressed from snorting – to IV – to smoking.
By looking at how the drug affects CNS activity one may determine why the abuse potential of cocaine is so high.
Cocaine Blocks Dopamine Re-Uptake
Piriform Cortex
NucleusAccumbens
Amygdala
Septum
Striatum
Frontal Cortex
High levels of dopamine in the limbic system are associated with feelings of intense pleasure – especially the nucleus accumbens; the site associated with reward and locomotor stimulation
Cocaine Blocks Serotonin Re-Uptake
Hypothalmus
Amygdala
CorpusStriatum
SubstantiaNigra
Cerebellum
Cerebrum
High serotonin levels enhance the reward activity of elevated dopamine in Nucleus Accumbens
Serotonin receptors are hypersensitive during cocaine withdrawal – especially in amygdala
Withdrawal from cocaine leads to a substantial reduction in serotonin release.
Decreased serotonin is associated with depression, panic disorder, insomnia, impulsiveness and a hyper-aggression behavior disorder.
Cocaine Blocks Norepinephrine Re-Uptake
CerebralCortex
Cerebellum
Hippocampus
Amygdala
Hypothalmus
High levels of NE are associated with the feelings of arousal and with high doses may be responsible for the “Rush”. Increased NE enhances the dopamine effects on locomotor stimulation
Cocaine and Ethanol – A Real Problem
Alcohol potentiates the cocaine-induced euphoria and diminishes the undesirable effects of cocaine withdrawal. Most cocaine addicts also abuse ethanol with as much as 77 percent using ethanol and cocaine simultaneously and thirty percent reporting using ethanol and cocaine together every time.
Cocaine is normally metabolized to benzoylecgonine by a liver (lung & heart) carboxylesterase
In the presence of ethanol, however, it is made into cocaethylene.
Cocaethylene:
~ 25x death incidence vs. cocaine alone
Hypertension due to increased vascular resistance
Decreased myocardial function ( SV)
Decreased myocardial conduction & Arrhythmogenic – blocks Na+ channels much more effectively than cocaine.
Cocaine - Crack – Crime(from: Goldstein, Inciardi/Pottieger, Fagan, Chin)
Systemic Crime - Resulting from the system of drug distribution, “economic regulation and control”: majority of drug-related homocides
Psychopharmacologically Driven Crime – Resulting from drug use: 5% or less
Economically Compulsive Crime – financially driven to crime by financial realities of the drug use; ~ 98% of crimes comprise drug sales to support habit, ~ half users commit one property crime/week (shoplifting), prostitution