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Substance Abuse and Addiction Health Center

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Methamphetamine - Topic Overview

Methamphetamine is a powerful stimulant, used medically to treat sleep problems (narcolepsy), attention deficit hyperactivity disorder (ADHD), and severe overweight problems. The illegal form of methamphetamine is a white, odorless, bitter-tasting, crystalline powder that can be dissolved easily in water or alcohol. It is called speed, meth, ice, crystal, glass, or chalk. The smoked form of methamphetamine is often called ice, crystal, crank, or glass. Illegal methamphetamine is often made in makeshift laboratories from inexpensive ingredients.

Methamphetamine can be smoked, snorted, swallowed, or injected. When it is smoked or injected, the person feels an intense pleasurable rush that lasts only a few minutes. The smokable form produces an odorless smoke that leaves a residue that can be smoked again, allowing the person to experience effects of the drug for up to 12 hours or more. When it is snorted or taken by mouth, the person feels happy (euphoric) but does not have the intense rush obtained from smoking or injecting the drug. People who abuse this drug have a tendency to use it repeatedly (binge) and then crash afterward.

In small doses, methamphetamine can increase wakefulness and physical activity and decrease appetite. In high doses, it can increase body temperature to dangerous-and possibly deadly-levels, as well as cause seizures. Because methamphetamine increases heart rate and blood pressure, it can permanently damage blood vessels in the brain, causing a stroke. People who abuse methamphetamine may become anxious, confused, and violent. They may develop serious psychological effects, such as paranoia, seeing or hearing things that are not present (hallucinations), and believing things that are not true (delusions).

Methamphetamine is highly addictive. If use is stopped, it can lead to depression, anxiety, and paranoia. Also, the person usually has strong cravings for the drug.

Methamphetamine's high lasts from 8 to 24 hours. The drug can be detected in a urine drug screen up to 48 hours after use.

Signs of use

  • Long periods of time without eating or sleeping
  • Agitated behavior, excited speech, irritability, nervousness, and increased physical activity
  • Wide pupils and increased pulse rate

    WebMD Medical Reference from Healthwise

    Last Updated: March 12, 2014
    This information is not intended to replace the advice of a doctor. Healthwise disclaims any liability for the decisions you make based on this information.
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