Effects of drugs
The National Institute on Drug Abuse describes the addictive and health effects of some of the most commonly abused drugs.
Cocaine
A powerfully addictive drug that is snorted, sniffed, injected, or smoked. Crack is cocaine that has been processed from cocaine hydrochloride to a free base for smoking. Cocaine usually makes the user feel euphoric and energetic. Common adverse health effects include heart attacks, respiratory failure, strokes, and seizures. Large amounts can cause bizarre and violent behavior. In rare cases, sudden death can occur on the first use of cocaine or unexpectedly thereafter.
MDMA/Ecstasy
A drug that has stimulant and psychedelic properties. It is taken orally as a capsule or tablet. Short-term effects include feelings of mental stimulation, emotional warmth, enhanced sensory perception, and increased physical energy. Adverse health effects can include nausea, chills, sweating, teeth clenching, muscle cramping, and blurred vision.
Heroin
An addictive drug that is processed from morphine and usually appears as a white or brown powder. Short-term effects include a surge of euphoria followed by alternately wakeful and drowsy states and cloudy mental functioning. It is associated with fatal overdose and, particularly in users who inject the drug, infectious diseases such as HIV/AIDS and hepatitis.
Inhalants
Breathable chemical vapors that users intentionally inhale because of the chemicals' mind-altering effects. The substances inhaled are often common household products that contain volatile solvents or aerosols. Most inhalants produce a rapid high that resembles alcohol intoxication. If sufficient amounts are inhaled, nearly all solvents and gases produce a loss of sensation, and even unconsciousness.
LSD/Acid
One of the strongest mood-changing drugs. It is sold as tablets, capsules, liquid, or on absorbent paper. It produces unpredictable psychological effects. With large enough doses, users experience delusions and visual hallucinations. Physical effects include increased body temperature, heart rate, and blood pressure; sleeplessness; and loss of appetite.
Marijuana
In 2011, Marijuana was the most commonly used illegal drug in the U.S. The main active chemical is THC. Short-term effects include memory and learning problems, distorted perception, and difficulty thinking and solving problems.
Methamphetamine
An addictive stimulant that is closely related to amphetamine, but has longer-lasting and more toxic effects on the central nervous system. It has a high potential for abuse and addiction. Increases wakefulness and physical activity and decreases appetite. Chronic, long-term use can lead to psychotic behavior, hallucinations, and stroke.
Nicotine/Tobacco
A highly addictive drug and one of the most heavily used in the U.S. Smoking harms nearly every organ of the body, causing many diseases including cancer, emphysema and other respiratory illnesses, and heart disease. The adverse health effects from cigarette smoking account for thousands of deaths each year in the U.S.
PCP/Phencyclidine
Illegally manufactured in labs and sold as tablets, capsules, or colored powder. Also known as angel dust, it can be snorted, smoked, or eaten. Developed in the 1950s as an IV anesthetic, PCP was never approved for human use because of problems during clinical studies, including intensely negative psychological effects. Many PCP users are brought to emergency rooms because of overdose or because of the drug's unpleasant psychological effects. People high on PCP often become violent or suicidal.
Prescription medications
Prescription drugs that are abused or used for nonmedical reasons can alter brain activity and lead to dependence. Commonly abused classes of prescription drugs include opioids (often prescribed to treat pain), central nervous system depressants (often prescribed to treat anxiety and sleep disorders), and stimulants (prescribed to treat narcolepsy, ADHD, and obesity). Long-term use of opioids or central nervous system depressants can lead to physical dependence and addiction. Taken in high doses, stimulants can lead to compulsive use, paranoia, dangerously high body temperatures, and irregular heartbeat.