Stimulants are a class of drugs that elevate mood, increase feelings of well-being, and increase energy and alertness.
Examples include cocaine, methamphetamine, amphetamines, methylphenidate, nicotine, and MDMA (3,4-methylenedioxymethamphetamine), better known as “Ecstasy.”
Cocaine comes in two forms. Powder cocaine is a hydrochloride salt, made from the leaf of the coca plant. “Crack” is a smokeable form of cocaine that is processed with ammonia or baking soda and water, and heated to remove the hydrochloride.
Methamphetamine is a powerful stimulant, originally derived from amphetamine. It comes in clear crystals or powder and easily dissolves in water or alcohol. Although most of the methamphetamine used in the United States comes from “superlabs,” it is also made in small laboratories using inexpensive over-the-counter and often toxic ingredients (such as drain cleaner, battery acid, and antifreeze).
Amphetamines, such as Adderall, are stimulants that often come in pill form and are sometimes prescribed by doctors for medical problems, most commonly attention deficit hyperactivity disorder (ADHD). Amphetamines can also be abused—that is, used in a way or for a purpose other than as prescribed (e.g., crushed and snorted, "to get high") or used by someone without a prescription.
Methylphenidate, such as Concerta or Ritalin, is another medication prescribed for people with ADHD. As seen with amphetamines, including Adderall, numerous studies have shown its effectiveness when used as prescribed. When it is abused, however, methylphenidate can lead to many of the same problems seen with other stimulants. Find out more about prescription drug abuse.
Cocaine is generally sold on the street as a fine, white, crystalline powder, known as “coke,” “C,“ “snow,” “flake,“ “blow,” “bump,“ “candy,“ “Charlie,” “rock,” and “toot.” “Crack,” the street name for the smokeable form of cocaine, got its name from the crackling sound made when it’s smoked. A “speedball” is cocaine or crack combined with heroin, or crack and heroin smoked together.
Methamphetamine is commonly known as “speed,” “meth,” “chalk,” and “tina.” In its smokeable form, it’s often called “ice,” “crystal,” “crank,” “glass,” “fire,” and “go fast.”
Street names for amphetamines include “speed,” “bennies,” “black beauties,” “crosses,” “hearts,” “LA turnaround,” “truck drivers,” and “uppers.”
Street names for methylphenidate include “rits,” “vitamin R,” and “west coast.”
Stimulants are abused in several ways, depending on the drug. They can be:
- Swallowed in pill form.
- Snorted in powder form through the nostrils, where the drug is absorbed into the bloodstream through the nasal tissues.
- Injected, using a needle and syringe, to release the drug directly into a vein.
- Heated in crystal form and smoked (inhaled into the lungs).
Injecting or smoking a stimulant produces a rapid high—or rush—because the drug is absorbed into the bloodstream quickly, intensifying its effects. Snorting or swallowing stimulants produces a high that is less intense but lasts longer.
Powder cocaine is usually snorted or injected (also called “mainlining”), or it can be rubbed onto mucous tissues, such as the gums. Street dealers generally dilute cocaine with other substances (such as cornstarch, talcum powder, or sugar), with active drugs (such as procaine, a chemical that produces local anesthesia), or with other stimulants (such as amphetamines). Crack cocaine is often smoked in a glass pipe.
Methamphetamine is swallowed, snorted, injected, or smoked. “Ice,” a smokeable form of methamphetamine, is a large, usually clear crystal of high purity that is smoked, like crack, in a glass pipe.
Amphetamines and methylphenidate are usually swallowed in pill form.
In 2012, a NIDA-funded study reported that the following percentages of 8th, 10th, and 12th graders had abused these drugs at least once in the past year:
- Powder cocaine: 1.0 percent of 8th graders, 1.8 percent of 10th graders, and 2.4 percent of 12th graders
- Crack cocaine: 0.6 percent of 8th graders, 0.8 percent of 10th graders, and 1.2 percent of 12th graders
- Methamphetamine: 1.0 percent of 8th graders, 1.0 percent of 10th graders, and 1.1 percent of 12th graders
- Amphetamines: 2.9 percent of 8th graders, 6.5 percent of 10th graders, and 7.9 percent of 12th graders
- Nonmedical use of Ritalin: 0.7 percent of 8th graders, 1.9 percent of 10th graders, and 2.6 percent of 12th graders
- Nonmedical use of Adderall: 1.7 percent of 8th graders, 4.5 percent of 10th graders, and 7.6 percent of 12th graders
Stimulants change the way the brain works by changing the way nerve cells communicate. Nerve cells, called neurons, send messages to each other by releasing chemicals called neurotransmitters. Neurotransmitters work by attaching to key sites on neurons called receptors.
Learn more about how neurotransmitters work in the section “How Does Your Brain Communicate?”
There are many neurotransmitters, but dopamine is the main one that makes people feel good when they do something they enjoy, like eating a piece of chocolate cake or riding a roller coaster. Stimulants cause a buildup of dopamine in the brain, which can make people who abuse stimulants feel intense pleasure and increased energy. They can also make people feel anxious and paranoid. And with repeated use, stimulants can disrupt the functioning of the brain’s dopamine system, dampening users’ ability to feel any pleasure at all. People may try to compensate by taking more and more of the drug to experience the same pleasure.
In the short term, stimulants can produce feelings of tremendous joy, increased wakefulness, and decreased appetite. People who abuse them can become more talkative, energetic, or anxious and irritable. Other short-term effects of stimulants can include increased body temperature, heart rate, and blood pressure; dilated pupils; nausea; blurred vision; muscle spasms; and confusion.
Stimulants can also cause the body’s blood vessels to narrow, constricting the flow of blood, which forces the heart to work harder to pump blood through the body. The heart may work so hard that it temporarily loses its natural rhythm. This is called fibrillation and can be very dangerous because it stops the flow of blood through the body.
As with many other drugs of abuse, repeated stimulant abuse can cause addiction. That means that someone repeatedly seeks out and uses the drug despite its harmful effects. Repeated drug use changes the brain in ways that contribute to the drug craving and continued drug seeking and use that characterizes addiction. Other effects of long-term stimulant abuse can include paranoia, aggressiveness, extreme anorexia, thinking problems, visual and auditory hallucinations, delusions, and severe dental problems.
Repeated use of cocaine can lead to tolerance of its euphoric effects, causing the person to take greater amounts or to use the drug more frequently (e.g., binge use) to get the same effects. Such use can lead to bizarre, erratic behavior. Some people who abuse cocaine experience panic attacks or episodes of full-blown paranoid psychosis, in which the individual loses touch with reality and hears sounds that aren’t there (auditory hallucinations). Different ways of using cocaine can produce different adverse effects. For example, regularly snorting cocaine can lead to hoarseness, loss of the sense of smell, nosebleeds, and a chronically runny nose. Cocaine taken orally can cause reduced blood flow, leading to bowel problems.
Repeated use of methamphetamine can cause violent behavior, mood disturbances, and psychosis, which can include paranoia, auditory hallucinations, and delusions (e.g., the sensation of insects creeping on the skin, called “formication”). The paranoia can result in homicidal and suicidal thoughts. Methamphetamine can increase a person’s sex drive and is linked to risky sexual behaviors and the transmission of infectious diseases, such as HIV. However, research also indicates that long-term methamphetamine use may be associated with decreased sexual function, at least in men.
Yes, in rare instances, sudden death can occur on the first use of cocaine or unexpectedly thereafter. And, like most drugs, stimulants can be lethal when taken in large doses or mixed with other substances. Stimulant overdoses can lead to heart problems, strokes, hyperthermia (elevated body temperature), and convulsions, which if not treated immediately can result in death. Abuse of both cocaine and alcohol compounds the danger, increasing the risk of overdose.
They act in different ways to increase dopamine in the brain. Cocaine works by blocking the dopamine transporter; that is, it doesn’t allow dopamine to be recycled back into the neuron after it has done its work. Methamphetamine interferes with this recycling process as well, but it also causes too much dopamine to be released. Another difference is that cocaine disappears from the brain quickly, while methamphetamine stays much longer. The long presence in the brain ultimately makes methamphetamine very harmful to brain cells.
In the United States, 20.9 percent of pregnant teens age 15 to 17 reported past-month use of an illicit drug (based on combined data from 2010-2011). Scientists have found that exposure to cocaine during fetal development may lead to subtle but significant deficits later in life, including problems with attention and information processing—abilities that are important for success in school. Research is also underway on the effects of methamphetamine use during pregnancy. So far, the data suggest that it may affect fetal growth and contribute to poor quality of movement in infants.
Research in this area is particularly difficult to interpret because it is often hard to single out a drug’s specific effects among the multiple factors that can all interact to affect maternal, fetal, and child outcomes. These factors include exposure to all drugs of abuse, including nicotine and alcohol; extent of prenatal care; possible neglect or abuse of the child; exposure to violence in the environment; socioeconomic conditions; maternal nutrition; other health conditions; and exposure to sexually transmitted diseases.
Several behavioral therapies are effective in treating addiction to stimulants. These approaches are designed to help the person think differently, change their expectations and behaviors, and increase their skills in coping with various stresses in life. One form that is showing positive results in people addicted to either cocaine or methamphetamine is called contingency management, or motivational incentives (MI). These programs reward patients who refrain from using drugs by offering vouchers or other small rewards. MI may be particularly useful for helping patients to initially stop taking the drug and for helping them to stay in treatment.
Currently, there are no medications approved by the U.S. Food and Drug Administration to treat people who are addicted to stimulants, although that is an active area of research for NIDA.
When someone has a drug problem, it's not always easy to know what to do. If someone you know is abusing stimulants, encourage him or her to talk to a parent, school guidance counselor, or other trusted adult. There are also anonymous resources, such as the National Suicide Prevention Lifeline (1-800-273-TALK) and the Treatment Referral Helpline (1-800-662-HELP).
The National Suicide Prevention Lifeline (1-800-273-TALK) is a crisis hotline that can help with a lot of issues, not just suicide. For example, anyone who feels sad, hopeless, or suicidal; family and friends who are concerned about a loved one; or anyone interested in mental health treatment referrals can call this Lifeline. Callers are connected with a professional nearby who will talk with them about what they’re feeling or concerns for other family and friends.
In addition, the Treatment Referral Helpline (1-800-662-HELP)—offered by the Substance Abuse and Mental Health Services Administration—refers callers to treatment facilities, support groups, and other local organizations that can provide help for their specific need. You can also locate treatment centers in your state by going to www.samhsa.gov/treatment.