Amphetamines are synthetic psychoactive drugs that stimulate or increase the action of the central nervous system. They are available legally by prescription and have been used medically to treat obesity, fatigue and depression. Today, medical use of amphetamines is limited to treating minimal brain dysfunction (MBD) in children and narcolepsy, a rare disorder in which an individual is overcome by sudden and uncontrollable attacks of deep sleep. Amphetamines have become a popular "street" drug. Legally produced amphetamines may be sold on the black market but quality and quantity of the drug may vary. Underground chemists have also developed a "look-alike" amphetamine that is being sold on the street. Look-alikes are drugs manufactured to look like real amphetamines and mimic their effects. They are sold on the street as "speed" or "uppers" and are expensive, even though they are a weak substitute for amphetamines. The drugs contain varying amounts of less potent stimulants such as caffeine, ephedrine and phenylpropanolamine-all legal substances that are usually found in over-the-counter diet pills and decongestants.

Dangers of look-alikes are that they are readily available and there is no way to know what they really contain. There have been reports of overdoses when users purchased real amphetamine they thought were look-alikes and use the amount they would have of look-alikes. Users of true amphetamines may also underestimate the potency of the look-alike drugs and take excessive amount that can result in toxic reactions.

 These signs may indicate the use of amphetamines:

• Dilated pupils

• Dry mouth and nose

•  Bad breath

• Frequent lip licking

• Excessive activity, difficulty sitting still, lack of interest in food or sleep

• Irritable, moody, nervous

• Argumentative

• Talkative

The effects of any drug depend on the amount taken, the user's past drug-use experience, circumstances in which the drug is taken (the place, feelings, activities, others involved) and the method of administration.

Small doses of amphetamines reduce appetite, increase respiration, heart rate, and blood pressure, and dilute the pupils. Moderate doses can cause dry mouth, fever, sweating, headache, blurred vision, dizziness, diarrhea, constipation, and loss of appetite.

Large doses of amphetamines may cause flushing, pallor, rapid and irregular heartbeat, tremors, loss of coordination or physical collapse. Injecting amphetamines creates a sudden increase in blood pressure that can cause death from stroke, high fever, or heart failure.

In addition to the physical effects of amphetamines, users report feeling restless, anxious and moody. Increased doses intensify the effects, and users may become exited or talkative and experience a false sense of self-confidence or superiority. They may behave in a bizarre manner; some become aggressive and hostile.

Prolonged use of amphetamines can lead to malnutrition and vitamin deficiencies, skin disorders, ulcers, lack of sleep, weight loss and depression. Frequent use of large amounts of amphetamines can cause brain damage that results in speech and thought disturbances.

Users of large amounts of amphetamines over a long period of time can develop an amphetamine psychosis, which is a mental disorder similar to paranoid schizophrenia. The psychosis is manifested by hallucinations, delusions, and paranoia. Those with amphetamine psychosis exhibit bizarre, sometime violent, behavior. Symptoms usually disappear within a few weeks after drug use stops.

Amphetamines have the potential to produce tolerance, which means that increased amounts of the drug are needed to achieve the desired effects. Withdrawal symptoms can occur when use of amphetamines is stopped abruptly. Users may experience fatigue; long, disturbed periods of sleep; irritability; intense hunger, and moderate to severe depression. The length and severity of the depression is related to how much and how often amphetamines were used.

Since withdrawal from prolonged amphetamine use is accompanied by physical and mental depression, and usually not life threatening or physically painful symptoms, the majority of amphetamine users who want to stop can be treated by encouraging abstinence. In fact, users should avoid all stimulants, including caffeine and tobacco.

Medical treatments include the use of antidepressant agents such as imipramine, desipramine, amitriptyline, dosepin, trazodone, or fluoxetine (Prozac). These affect serotonin, the neurotransmitter in the brain that deals with both depression and drug craving.

Sedatives such as Dalmane, chloral hydrate, Librium, phenobarbital, or even Valium are used, very carefully, on a short-term basis to treat anxiety or sleep disturbance problems. Antipsychotic medications such as Haldol, Thorazine, and others are also used to buffer the effects of unbalanced dopamine, the neurotransmitter that moderates paranoia and pleasurable sensation.

In addition to treating the physical and psychological aspects of craving, treatment providers should stress group counseling and peer pressure for compulsive amphetamine users, as these forms of therapy work well for this population.