A Guide to Methamphetamines

By The Fix staff 07/10/14

Methamphetamine is a highly addictive stimulant narcotic (also called meth, crystal, and ice, among other terms) that takes the form of a white, odorless, bitter-tasting crystalline powder. Methamphetamine stimulates the central nervous system and is similar in effect and creation to the drug amphetamine. It is seldom used for prescription purposes due to its addictive qualities and its serious long-term effects on the brain.

Its chemical makeup is n-methyl-1-phenyl-propan-2-amine, labeled methamphetamine, methyl amphetamine, or desoxyephedrine.

Synthesized in 1887 as amphetamine and soon after (1893) combined with ephedrine to create methamphetamine, this drug was typically used for weight loss and treatment of ADHD. Methamphetamine produces a surge of dopamine production in the brain, creating a sense of euphoria lasting up to 12 hours, depending on the method of use and the amount. When the sense of well-being produced by the drug wears off, a strong desire to repeat emerges and often leads to habitual and chronic use.

How is Methamphetamine Used?  

Methamphetamine is a Schedule II (highly restricted but not completely banned) narcotic by federal classification. Prescribed use of methamphetamine is limited to one fill. Due to its many dangerous side effects and its tendency to become quickly addictive, it is infrequently prescribed for treatment in certain cases of ADHD, obesity and sometimes narcolepsy. When used as prescribed, it is taken orally. When used illegally, owing to its potential for immediate effect, it is frequently smoked, snorted, injected, and dissolved in water. Because the euphoria fades quickly, users often take repeated doses.

How Methamphetamine Affects the Brain

Methamphetamine increases the amount of the neurotransmitter dopamine, leading to high levels in the brain. As a chemical messenger, dopamine is similar to adrenaline. It helps control the brain's reward and pleasure centers. Methamphetamine's ability to release dopamine rapidly in the rewards regions of the brain produces the euphoric rush for which it is famous as well as the desire for repeated use even in people aware of its addictive nature. 

Signs of Abuse

There is often a lack of self care associated with methamphetamine abuse, including going days without food or sleep. Long-term use has many negative consequences for physical health, including extreme weight loss, severe dental problems, and skin sores. Users experience high levels of alertness, leading to an inability to sleep, to hyperactivity, loss of appetite, aggressive behavior and irritability, anxiety, faster breathing, elevated blood pressure and heart rate, rapid or irregular heartbeat, and hyperthermia. 

Long-Term Effects of Abuse 

Besides the high risk of overdose, increased heart rates and high blood pressure, people who use methamphetamine long-term may experience unrelieved anxiety, confusion, insomnia, and mood disturbances. Violent behavior is not uncommon. Users may also show symptoms of psychosis, such as paranoia, visual and auditory hallucinations, and delusions. It is not uncommon to experience the sensation of insects crawling under the skin, causing intense scratching and picking. There is also a high risk of severe dental issues (meth mouth) and weight loss.

Chronic use causes chemical and molecular changes in the brain, altering the activity in the dopamine system and often reducing motor skills and impairing verbal learning. In studies of chronic users, severe structural and functional changes have been found in areas of the brain associated with emotion and memory which may cause emotional and cognitive problems. Many of these changes can persist long after use has stopped, although some may reverse after being off the drug for a sustained period.

Methamphetamine use also raises the risk of contracting infectious diseases like HIV and hepatitis B and C. These can be contracted both by sharing contaminated needles and unsafe sex. It alters judgement and inhibition and can lead people to engage in risky behaviors.

Methamphetamine Overdose

The symptoms of prolonged use of methamphetamine and the symptoms of an overdose are very similar. It can be difficult to know immediately when an overdose has occurred. Common symptoms are rapid pulse, higher heart rate, sweating, and shortness of breath, dilated pupils, and an increase in body temperature. Heart attacks are common with methamphetamine overdose, as are strokes and kidney failure. These symptoms can take place very quickly after ingesting the drug. They may occur too rapidly to be recognized as an overdose, causing sudden death.

If you or someone you are with show signs of a drug overdose, call emergency services immediately. 

Mixing with Other Drugs

Taking methamphetamine with cocaine or other stimulant drugs can have devastating outcomes. Combining methamphetamine with alcohol, marijuana, tobacco, or heroin increases the dangers of overdose and is toxic with long-term use.


Methamphetamine withdrawal consists of two phases. The first phase (acute phase) is most intense during the first 24 hours after you last use meth, and gradually gets less intense (protracted phase) over the course of about two weeks. Common symptoms experienced during the acute phase include irritability, intense drug cravings, depression, mood swings, agitation, anxiety, paranoia, hallucinations, fatigue, inability to concentrate, and body aches. The second phase lasts for about another two to three weeks, and is less intense. Symptoms that remain are cravings, problems with thinking and memory, sleep disorders and depression. Sometimes meth users experience withdrawal symptoms for months, known as post acute withdrawal syndrome (PAWS). Since addicts have typically gone long periods without sleep and food, detoxing from methamphetamine can cause high anxiety, body aches and pains and long periods of sleeping, sometimes several days.

Drug Tests

Methamphetamine remains detectable in the system for up to 90 days with certain tests.

Legal Status

As a Schedule II narcotic by U.S. federal classification, when not prescribed by a doctor, possession of any quantity is considered illegal. Similar laws apply in the UK and Canada.






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