Cocaine physiological effects

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... 

Cocaine inhibits the presynaptic reuptake of the neurotransmitters norepinehrine, serotonin, and dopamine at synaptic junctions. This results in increased concentrations in the synaptic cleft. Since norepinephrine acts within the sympathetic nervous system, increased sympathetic stimulation is produced. Physiological effects of this stimulation include tachycardia, vasoconstriction, mydriasis, and hyperthermia.3 CNS stimulation results in increased alertness, diminished appetite, and increased energy. The euphoria or psychological stimulation produced by cocaine is thought to be related to the inhibition of serotonin and dopamine reuptake. Cocaine also acts as a local anesthetic due to its ability to block sodium channels in neuronal cells.3... 

Physiologically, cocaine is a powerful stimulant that quickens the heartbeat, but it wears off much faster than heroin, which works to depress the heart rate. The stimulant effect of the cocaine and the depressant effect of heroin wreak havoc on the heart, which can lose its rhythm. Cocaine frequently masks how much heroin has been consumed, and when the cocaine s effects dissipate, heart failure can result. John Belushi and River Pheonix both died this way after taking speedballs. 

Because they both seem to function as uppers, some people think that cocaine and methamphetamine are essentially the same drug. While it is true that they both have similar mental and physiological effects, the two drugs do act quite differently. In contrast to cocaine, which is rapidly broken down in the body, methamphetamine tends to accumulate in both the body and brain, thereby leading to longer effects and more potential to cause long-term brain damage. Also, cocaine is derived from a natural substance, the coca plant, while methamphetamine is a totally synthetic chemical. 

Behavioural antecedents of a cocaine-induced stereotype33 and rate dependency of behavioral effects34 have been studied. Studies of the physiological effects on Man of intravenous administration of cocaine35 and of the discriminative response of humans to cocaine36 have given new results. 

Alkaloids are compounds of biosynthetic origin that contain nitrogen, usually in a heterocyclic ring. These compounds are produced by plants in which they are usually present as salts of organic acids. They tend to be basic and to have a variety of physiological effects. One of the more notorious alkaloids is cocaine, and alkaloidal strychnine is a deadly poison. The structural formulas of these compounds and three other alkaloids are given in Figure 15.10. 

The studied molecules include such diverse compounds as volatile anesthetics (halothane), local anesthetics of the cocaine type, calcium channel-blocking agents such as verapamil, antidepressants (chlorpromazine), and anti cancer drugs such as adriamycin. It is argued that the factor of interest to the physiological effect may not... 

Drugs such as cocaine and amphetamines that produce the physiological effects of sympathetic activity. 

Dependence may develop after chronic use of cocaine or amphetamines. The abstinence syndrome is characterized primarily by depression and craving with few measurable physiological effects. Thus, a drug that does not cause severe physical withdrawal symptoms can still be highly addictive. 

The physiological effects of LSD and related hallucinogens arc generally similar to those of amphetamine and cocaine that is, they are sympathotnimetic. Thus, the effects include pupil dilation, increased heart rate and blood pressure, increased body temperature, and increased sweating (Grinspoon Bakalar, 1979). 

These compounds possess potent physiological effects in animals and have long been of interest in medicine. Many have mydriatic activity (i.e., they cause dilation of the pupil of the eye). Others, such as cocaine, are anesthetics (Leete, 1990). 

Javaid, J.I. Fischman. M.W. Schuster, C.R. Dekirmenjian, H. and Davis, J.M. Cocaine plasma concentration Relation to physiological and subjective effects in humans. Science 202 227-228, 1978. 

Higgins, S.T. et al., Effects of intranasal cocaine on human learning, performance and physiology, Psychopharmacology, 102, 451, 1990. 

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