Cocaine free base

As discussed below in detail, first-principles electronic structure calculations have provided accurate predictions of the reaction pathways and the corresponding energy barriers, not only for the first step of hydrolysis of cocaine free base at the benzoyl ester group, but also for the entire reaction processes of hydrolysis of cocaine free base at both the benzoyl ester and methyl ester groups. 

Cocaine HCl is an alkaloid derived from the leaves of the South American coca plant. The free base alkaloid, made by extraction from cocaine HCl, is relatively insoluble in water, but dissolves in a variety of organic solvents. There has been a dramatic increase in the use of cocaine free base, which is most commonly known by its street name "crack". Since free base is not destroyed by heating, but rather vaporizes, it can be smoked and inhaled [129]. This provides speedy absorption from the respiratory tract inducing a short-lived but rapid euphoria. The free base is also well absorbed by nasal, vaginal, gastrointestinal and subhngual mucous membranes. Cocaine can be injected intravenously, intramuscularly or subcutaneously. Crack is often combined with heroin or other drugs of abuse and taken intravenously [128]. Cocaine is detoxified by cholinesterases and cocaine or its metabolites may be present in the urine for one to two days after use. 

Cocaine can have marked effects on the heart and cardiovascular system. Adverse actions may include myocardial ischemia, cardiac arrhythmias, cardiotoxicity, hypertensive effects, cerebrovascular events, and a hyperco-agulable state (24,40). By 1997 more than 250 cases of myocardial infarction related to the recreational use of cocaine had been documented in the literature (41). Although less common, aortic dissection related to use of cocaine-free base ("crackcocaine") has also been documented (42). Seizures also can be associated with cocaine use (43). 

Cocaine HCl is an alkaloid derived from the leaves of the South American coca plant. The free base alkaloid, made by extraction from cocaine HCl, is relatively insoluble in water, but dissolves in a variety of organic solvents. There has been a dramatic increase in the use of cocaine free base, which is most commonly known... 

Cocaine production Coca paste is dissolved in sulfuric acid to hydrolyze the alkaloids and produce ecognine. This is treated with 10% boron trichloride to produce ecognine methyl ester. Potassium permanganate is also added until the solution turns and remains pink. This removes cinnamoylcocaine isomers, which may be present in the mixture. The mixture is filtered, and the addition of base to the filtrate precipitates cocaine free base known as crack cocaine. The free base is dissolved in ether and precipitated as the hydrochloride salt through the addition of hydrochloric acid and is called snow cocaine. 

Cocaine (free base or salt form) is used as a local anesthetic, mainly for eye (cornea), nose, and throat during surgery. Owing to ocular toxicity, its use in ophthalmology is limited and it has been replaced by other agents (martindale). Coca leaf and its extracts are not used in pharmaceutical preparations in the United States. 

If (-) cocaine-HCl is substituted for (-) cocaine free base, the cocaine-induced behaviors are markedly reduced, because the HCl salt requires a much higher temperature to sublime, such that most of the cocaine is pyrrolized. 

Table 37.1 Behavioral Scoring of FHes following Exposure to Cocaine Free-base Vapors...

Crack is the free base form of cocaine which in contrast to cocaine, the salt form, can be smoked. This inhalative application results in a very rapid, intense effect. 

Crack cocaine A concentrated form of the drug (free base) formed by heating cocaine hydrochloride (the salt) with sodium bicarbonate Cocaine HCl + NaHC03 > Cocaine + NaCl + H20 + C02. 

Which of the following is associated with crack (the free-base form of cocaine) ... 

The answer is b. (Kn.lzu.ng, p 5.38.) Crack is the free-base (nonsalt) form of the alkaloid cocaine. It is called crack because, when heated, it makes a crackling sound. Heating crack enables a person to smoke it the drug is readily absorbed through the lungs and produces an intense euphoric effect in seconds Use has led to seizures and cardiac arrhythmias. Some of cocaine s effects (sympathomimetic) are due to blockade of norepinephrine reuptake into presynaptic terminals it does not block receptors. Flashbacks can occur with use of LSD and mescaline but have not been associated with the use of cocaine. 

Cocaine has structural and pharmacological similarities to the active constituents of belladonna and jimson weed and can likewise space you out in very undesirable ways, expecially if used frequently. Also, as with every drug, some people are very sensitive to it and can become paranoid, etc. with very little exposure. Cocaine base ( free base ) is much more euphorigenic than cocaine and consequently much more damaging. It seems to have the addictive pull of heroin for many users and is probably best avoided. 

A chemist from the Federal Bureau of Narcotics and Dangerous Drugs, who was in Bolivia to observe clandestine cocaine operations, related the following step-by-step procedure for manufacturing cocaine. The method can be conveniently divided into three major steps (1) extraction of cocaine from the leaf and chemical conversion to the sulfate (2) treatment of cocaine sulfate with potassium permanganate and conversion to the free base (aka paste) and (3) conversion of the paste or free base to cocaine hydrochloride. In general, steps (1) and (2) are carried out in sulfate labs while step (3) is performed in crystal labs. 

The addictiveness of a given substance goes beyond the chemical structure of the addictive drug itself (i.e., morphine, cocaine, or nicotine). The effects are also related to the dose and speed of delivery, as well as to other substances that might be part of the formulation. For example, just as the oral consumption of opioids and cocaine produce substantially less pronounced behavioral and physiological effects than intravenous or smoked consumption, slow release forms of nicotine produce generally less pronounced effects than smoked forms (Henningfield and Keenan 1993). Similarly, the free base or unprotonated forms of cocaine and... 

While some stimulants, such as amphetamine and methylphenidate, are taken orally, others are either volatilized for inhalation or snorted as the solid (nasal insufflation). It is necessary to convert cocaine and methamphetamine to their free base so that they can be volatilized. Methamphetamine and cocaine are also abused via the intravenous route. 

Cocaine hydrochloride is a water-soluble salt that can be injected or absorbed by any mucosal membrane (eg, nasal snorting). When heated in an alkaline solution, it is transformed into the free base, "crack cocaine," which can then be smoked. Inhaled crack cocaine is rapidly absorbed in the lungs and penetrates swiftly into the brain, producing an almost instantaneous "rush."... 

The extraction process can be performed in acidic conditions which produces the cocaine as its hydrochloride salt. Alkaline conditions will produce a lipophilic "free base" which can be extracted with a nonpolar solvent like ether. The ether can be volatilized with heat and the free base smoked, snorted, injected, or eaten. The salt form cannot be smoked. Cocaine paste, not common in the U.S. is a kerosene extract which may contain 20-90% cocaine sulfate. Crack is the result of free-basing with baking soda (sodium bicarbonate). The residual fillers and other impurities... 

Cocaine and amphetamines share a similar profile of addictiveness, though cocaines addictive properties are more intense. The cocaine that is inhaled nasally is the hydrochloride salt. The free-base form of cocaine, called crack cocaine, is also abused. As with the street drug ice, which is the free-base form of methamphetamine, crack cocaine is volatile and may be smoked for what is an intense but profoundly dangerous and addictive high. 

Perez-Reyes, M., DiGuiseppi, S, Ondrusek, G., Jeffcoat, A.R., and Cook, C.E., Free base cocaine smoking, Clin. Pharmacol. Ther , 32, 459 165, 1982. 

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