DRUGS 6
1-2lb Pharmacokinetics
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 (BE), the major metabolite, and other significant metabolites in lesser amounts such as ecgonine
methyl ester (EME) and ecgonine. Further minor metabolites of cocaine include norcocaine, p-hydroxycocaine,
m-hydroxycocaine, p-hydroxybenzoylecgonine (pOHBE), and m-hydroxybenzoylecgonine. If consumed with alcohol,
cocaine combines with alcohol in the liver to form cocaethylene.
Studies have suggested cocaethylene is both more euphoric, and has a higher cardiovascular toxicity than cocaine
by itself.
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.
1-2m Chemistry
1-2ma Appearance
A pile of cocaine hydrochloride
A piece of compressed cocaine powder
Cocaine in its purest form is a white, pearly product. Cocaine appearing in powder form is a salt, typically cocaine
hydrochloride. Street cocaine is often adulterated or “cut” with talc, lactose, sucrose, glucose, mannitol, inositol,
caffeine, procaine, phencyclidine, phenytoin, lignocaine, strychnine, amphetamine, or heroin.
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.
1-2n Forms
1-2na Salt
Cocaine is a weakly alkaline compound (an “alkaloid”), and can, therefore, combine with acidic compounds to form
various salts. The hydrochloride (HCl) salt of cocaine is by far the most commonly encountered, although the sulfate
(-SO4) and the nitrate (-NO3) are occasionally seen. Different salts dissolve to a greater or lesser extent in various
solvents – the hydrochloride salt is polar in character and is quite soluble in water.
1-2nb Base
As the name implies, “freebase” is the base form of cocaine, as opposed to the salt form. It is practically insoluble in
water whereas hydrochloride salt is water-soluble.
Smoking freebase cocaine has the additional effect of releasing methylecgonidine into the user’s system due to
the pyrolysis of the substance (a side effect which insufflating or injecting powder cocaine does not create).
Some research suggests that smoking freebase cocaine can be even more cardiotoxic than other routes of
administrationbecause of methylecgonidine’s effects on lung tissue and liver tissue.
Pure cocaine is prepared by neutralizing its compounding salt with an alkaline solution which will precipitate to
non-polar basic cocaine. It is further refined through aqueous-solvent liquid-liquid extraction.
1-2nc Crack cocaine
Crack is a lower purity form of free-base cocaine that is usually produced by neutralization of cocaine hydrochloride
with a solution of baking soda (sodium bicarbonate, NaHCO3) and water, producing a very hard/brittle, off-
white-to-brown colored, amorphous material that contains sodium carbonate, entrapped water, and other by-products
as the main impurities.
The “freebase” and “crack” forms of cocaine are usually administered by vaporization of the powdered substance
into smoke, which is then inhaled.
The origin of the name “crack” comes from the “crackling” sound (and hence the onomatopoeic moniker “crack”)
that is produced when the cocaine and its impurities (i.e. water, sodium bicarbonate) are heated past the point
of vaporization.
Pure cocaine base/crack can be smoked because it vaporizes smoothly, with little or no decomposition at 98 °C
(208 °F), which is below the boiling point of water.
In contrast, cocaine hydrochloride does not vaporize until heated to a much higher temperature (about 197 °C), and
considerable decomposition/burning occurs at these high temperatures. This effectively destroys some of the
cocaine and yields a sharp, acrid, and foul-tasting smoke.
Smoking or vaporizing cocaine and inhaling it into the lungs produces an almost immediate “high” that can be
very powerful (and addicting) quite rapidly – this initial crescendo of stimulation is known as a “rush”.
While the stimulating effects may last for hours, the euphoric sensation is very brief, prompting the user
to smoke more immediately.
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