Stimulants are also divided into multiple types such as Amphetamines and Cocaine as well as the more socially acceptable Caffeine and Nicotine. .
While the majority of psychotropic categories serve legitimate medical purposes, many of these chemicals have high addictive potentials. "Many addictive substances bind to receptors for the neurotransmitter dopamine, in a brain region called the nucleus accumbens. " Sheir et al ,2002).
With repeated use, the number of receptors targeted can decline. This means that the person must use more of the drug to feel the same effect. The more common term for this effect is tolerance.
Not all psychotropic affect the body chemistry in the same way. Amphetamines enhances norepinephrine activity (a neurotransmitter that controls arousal, dreaming and mood) thereby heightening alertness and mood.
Amphetamine's structure is so similar to that of norepinephrine that it binds to norepinephrine receptors and triggers the same changes in the postsynaptic membrane.
Cocaine has a complex mechanism of action, both blocking reuptake of norepinephrine and binding to molecules that transport dopamine to postsynaptic cells. Cocaine's rapid and short-lived "high" reflects its short stay in the brain-its uptake takes just four to six minutes, and within twenty minutes the drug loses half its activity.
GABA is an inhibitory neurotransmitter used in a third of the brain's synapses. The drug valium causes relaxation and inhibits seizures and anxiety by helping GABA bind to the receptors on postsynaptic neurons. (Sheir et al 2002).
The cost of addiction and recovery treatments in the United States has been enormous A study prepared for the National Institute on Drug Abuse and the National Institute on Alcohol Abuse and Alcoholism estimated the total economic cost of alcohol and drug abuse to be $245.7 billion for 1992. This estimate includes treatment and prevention costs and other healthcare costs.