Introduction
As Elizabeth Hartney argues ‘psychoactive’ is a term that is applied to drugs and substances that a change a personal mental state by affecting the way the brain and nervous system’s work. This can lead to intoxication which is often the main reason people choose to take psychoactive drugs. In some situations, however these drugs can be used to alter a person’s mental state in order to exploit them for example use of date rape drugs. Psychoactive drugs such as anti-depressants and drugs used to treat conditions such as ADHD are also psychoactive. Another author argues, “These are drugs since ancient times which were used for their psychological effects to stimulate or relax, to bring sleep or prevent it, to enhance ordinary perceptions or to produce hallucinations. They also include alcohol, tobacco and coffee.”(Atkinson, Richard & HIlgard, 1983). Another source describes psychoactive drugs as, “The term ‘drug’ refers to any chemical substance, aside from food, that, upon entering the body, alters the physical or chemical characteristics of the body and its functions. A drug that alters sensory perceptions, mood, thought processes, or behavior is known as a psychoactive drug.” Behavior according to psychology refers to any action for example eating, sneezing, gambling, learning a language.
DEPRESSANTS
In small quantities, it appears to increase people’s energy and make them feel lively and sociable. In reality alcohol is a central nervous system depressant, not a stimulant. The feeling of stimulation comes from its ability to relax some of the ordinary restraints on behavior. At concentrations of .03 to .05 percent in the blood, alcohol produces light headedness, relaxation and release of inhibitions. People say things they might not ordinarily say; they tend to become more sociable and sometimes show off. Users of alcohol after taking at a concentration of 1 percent (Say after three cocktails or three bottles of beer), sensory and motor functions become noticeably impaired. Speech becomes slurred; and there may be difficulty coordinating arm and leg movement. Depressants affect the behavior of those who use it because some people tend to become angry and aggressive, whereas others grow silent and morose.
There are other effects of alcohol which include loss of memory for what happened. Hallucinations (imaginary experiences with perpetual reality are also associated with excessive use of alcohol. * Heroin opium and its derivatives, collectively known as opiates, are drugs that diminish physical sensation and the capacity to respond to stimuli by depressing the central nervous system. These drugs are usually known as narcotics but ‘opiates’ is the more accurate term. Opiates are medically used for their pain killing properties. Their ability to alter mood and reduce anxiety has led to widespread illegal, nonmedical consumption. At first use of heroin produces a sense of well-being. Unlike the alcoholic, a heroine user can readily produce skilled responses to agility and intellectual tests and seldom becomes aggressive or assaultive. It is the changes in mood or self-confidence and the sensation of reduced anxiety.
STIMULANTS
Stimulants tend to increase activity in the brain. These drugs are known to temporarily elevate mood alertness and awareness. Freud who had used cocaine regarded it as favorable and encouraged its use he states that, “the exhilaration and lasting euphoria which in no way differs from the normal euphoria of the healthy person…… you can perceive an increase of self-control and possess more vitality and capacity for work…. In other words, you are simply normal and it is so hard to believe that you are under the influence of any drug…. Long intensive mental or physical work is performed without any fatigue ……This result is enjoyed without any of the unpleasant after effects that follow exhilaration brought about by alcohol…… Absolutely no craving for the further use of cocaine appears after the first or even repeated taking of the drug; one feels rather a curious aversion to it.” (1974, p9). Freund soon withdrew this unreserved support, however, for he treated a friend with cocaine and the results were disastrous. The friend developed severe addiction, demanded larger doses of the drug than Freud ever recommended, and we debilitated until his death * Amphetamines In contrast to depressants, are drugs that are increase arousal. They immediate consumption of these drugs is an increase in alertness and wakefulness and decrease in feelings of fatigue and boredom. Strenuous activities that require effort and endurance may become easier. Even though some these drugs are legal they lead to addiction. * Cocaine increases energy and self-confidence and decreases fatigue and appetite * Methylphenidate such as concerta and Ritalin is another medication prescribed for people with ADHD which is a problem with inattentiveness, over-activity, or a combination. For these problems to be diagnosed they must be out of the normal range for a child’s age and development. * Nicotine and MDMA also are considered stimulants.
Stimulants can be abused in different ways: * They can be swallowed in pill form * They can be sniffed through the nostrils * They can be injected using a needle and syringe directly into the vein * They can also be heated in crystal form and smoked.

HALLUCINOGENS
According to National institute of Drug abuse (NIDA), these compounds are found in some plants and mushrooms (or their extracts) have been used mostly during religious rituals for centuries. Almost all hallucinogens have chemical structures similar to those of natural neurotransmitters and so they work partially by interfering with the neurotransmitter action or by binding to their receptor sites. Some of the common hallucinogens are: * LCD (d-lysergic and diethylamide) The National institute of Drug abuse state that it is one of the most potent mood changing chemicals. It was discovered in 1938 and is manufactured from lysergic acid, which is found in ergot, a fungus that grows on rye and other grains * Peyote is a small spineless cactus In which cactus in which the principal active ingredient is mescaline * Psilocybin (4-phosphoryloxy-N,N-dimethyltryptamine) is obtained from certain types of mushrooms that are indigenous to tropical and subtropical regions of South America, Mexico and the United States * PCP (phencyclidine) was developed in the 1950s as an intravenous anesthetic. Its use has since been discontinued due to serious adverse effects. * Marijuana according to Atkinson, Richard & Hilgard, it is the most popular of all the illicit drugs and it is derived from the hemp plant users smoke or eat the leaves to induce a relaxed state of heightened perceptiveness. The authors argue that, “the active ingredient in marijuana is THC (tetrahydrocanabinol) taken orally in small doses (5-10mg) produces a ‘high’; larger doses(30-70mg) produce severe and longer lasting reactions that resemble those of more strongly hallucinogenic drugs. “