A stimulant is any drug or substance that speeds up the central nervous system. Stimulants, which are the opposites of depressants, make you feel alert and awake, and increase mental and physical energy. All of them are habit-forming, and some are highly addictive.
Some common substances, such as alcohol or nicotine, can work as either a stimulant and depressant, depending on how you consume them. For example, small amounts of alcohol can have a stimulating effect, but large amounts depress the nervous system.
A majority of American adults use common stimulants, such as coffee, tea and other caffeinated drinks, throughout their day without many harmful effects. Stronger stimulants, such as "energy drinks" or over-the-counter pills like "No-Doz," are often used on a short-term basis to enhance performance. For example, some truckers use them when they have to drive all night, and some college students use them to stay awake during late night study sessions.
Certain prescription stimulants have medical uses. Amphetamines are used to treat narcolepsy, and cocaine can be used as a topical anesthetic. Children with Attention Deficit Hyperactivity Disorder frequently take prescription stimulants, which have the paradoxical effect of calming them. Because millions of people are now taking prescription stimulants, they are widely available and widely abused.
Strong stimulants, such as methamphetamine, MDMA (Ecstasy), and cocaine, are extremely addictive. Some are illegal to use without a prescription or simply illegal to use at all. They are among the most highly abused drugs because they are so highly addictive.
Side effects of taking stimulants can be increased blood pressure and body temperature, hyperactivity, loss of appetite, dizziness, tremor, headache, flushed skin, chest pains with palpitations, excessive sweating, vomiting and abdominal cramps. Methamphetamine addicts can exhibit problems such as picking at imaginary sores, agitation, hostility, panic, aggression, and suicidal or homicidal tendencies. Stimulants can make it possible for people to go days without eating or sleeping, but afterward such marathons, they often experience severe problems, such as paranoia and hallucinations. These drugs can impair judgment and cause people to engage in risky behaviors.
When people become physically addicted to strong stimulants, they will experience withdrawal symptoms, such as depression, fatigue, loss of interest or pleasure in daily activities, insomnia, loss of appetite, suicidal thoughts and behavior, and paranoid delusions. If the addiction has been ongoing for a long time and involved large amounts of drugs, the person will likely need to enter a residential treatment center for detoxification under medical supervision. Then he will usually undergo psychotherapy and education about how to handle life without drugs.