Methamphetamine
What Is It?
Methamphetamine is a powerful, highly addictive stimulant that affects the central nervous system. It takes the form of a white, odorless, bitter-tasting crystalline powder that easily dissolves in water or alcohol.
Alternative Names
Desoxyn, Methedrine, N-methylamphetamine, N,α-dimethylphenethylamine, desoxyephedrine, Meth, Speed, Ice, Shards, Bikers Coffee, Stove Top, Tweak, Yaba, Trash, Chalk, Crystal, Crank, Shabu.
Legality
Methamphetamine has been classified by the U.S. Drug Enforcement Administration as a Schedule II stimulant, which makes it legally available only through a nonrefillable prescription. Medically it may be indicated for the treatment of attention deficit hyperactivity disorder (ADHD) and as a short-term component of weight-loss treatments, but these uses are limited and it is rarely prescribed; also, the prescribed doses are far lower than those typically misused.
Common Forms
White powder or pill; crystal meth looks like pieces of glass or shiny blue-white “rocks” of different sizes.
Common Ways Taken
Swallowed, snorted, smoked, injected.
Short Term Effects
Increased wakefulness and physical activity; decreased appetite; increased breathing, heart rate, blood pressure, temperature; irregular heartbeat.
Long Term Effects
Anxiety, confusion, insomnia, mood problems, violent behavior, paranoia, hallucinations, delusions, weight loss, severe dental problems, intense itching leading to skin sores from scratching.
As is the case with many drugs, tolerance to methamphetamine’s pleasurable effects develops when it is taken repeatedly. Abusers often need to take higher doses of the drug, take it more frequently, or change how they take it in an effort to get the desired effect. Chronic methamphetamine abusers may develop difficulty feeling any pleasure other than that provided by the drug, fueling further abuse. Withdrawal from methamphetamine occurs when a chronic abuser stops taking the drug; symptoms of withdrawal include depression, anxiety, fatigue, and an intense craving for the drug.
In addition to being addicted to methamphetamine, people who use methamphetamine long term may exhibit symptoms that can include significant anxiety, confusion, insomnia, mood disturbances, and violent behavior. They also may display a number of psychotic features, including paranoia, visual and auditory hallucinations, and delusions (for example, the sensation of insects creeping under the skin). Psychotic symptoms can sometimes last for months or years after a person has quit using methamphetamine, and stress has been shown to precipitate spontaneous recurrence of methamphetamine psychosis in people who use methamphetamine and have previously experienced psychosis.
Neuroimaging studies have demonstrated alterations in the activity of the dopamine system that are associated with reduced motor speed and impaired verbal learning. Studies in chronic methamphetamine users have also revealed severe structural and functional changes in areas of the brain associated with emotion and memory, which may account for many of the emotional and cognitive problems observed in these individuals.
Research in primate models has found that methamphetamine alters brain structures involved in decision-making and impairs the ability to suppress habitual behaviors that have become useless or counterproductive. The two effects were correlated, suggesting that the structural change underlies the decline in mental flexibility.12 These changes in brain structure and function could explain why methamphetamine addiction is so hard to treat and has a significant chance of relapse early in treatment.
Function in other brain regions did not recover even after 14 months of abstinence, indicating that some methamphetamine-induced changes are very long lasting. Methamphetamine use can also increase one’s risk of stroke, which can cause irreversible damage to the brain. A recent study even showed higher incidence of Parkinson’s disease among past users of methamphetamine.
Other health-related Issues
Pregnancy: premature delivery; separation of the placenta from the uterus; low birth weight; lethargy; heart and brain problems.
Risk of HIV, hepatitis, and other infectious diseases from shared needles.
In addition to the neurological and behavioral consequences of methamphetamine misuse, long-term users also suffer physical effects, including weight loss, severe tooth decay and tooth loss, and skin sores. The dental problems may be caused by a combination of poor nutrition and dental hygiene as well as dry mouth and teeth grinding caused by the drug. Skin sores are the result of picking and scratching the skin to get rid of insects imagined to be crawling under it.
When Combined With Alcohol
Masks the depressant effect of alcohol, increasing risk of alcohol overdose; may increase blood pressure.
Withdrawal Symptoms
Depression, anxiety, tiredness.
Additional Information
Smoking or injecting methamphetamine puts the drug very quickly into the bloodstream and brain, causing an immediate, intense "rush" and amplifying the drug’s addiction potential and adverse health consequences. The rush, or "flash," lasts only a few minutes and is described as extremely pleasurable. Snorting or oral ingestion produces euphoria—a high, but not an intense rush. Snorting produces effects within 3 to 5 minutes, and oral ingestion produces effects within 15 to 20 minutes.
As with many stimulants, methamphetamine is most often misused in a "binge and crash" pattern. Because the pleasurable effects of methamphetamine disappear even before the drug concentration in the blood falls significantly, users try to maintain the high by taking more of the drug. In some cases, people indulge in a form of binging known as a "run," foregoing food and sleep while continuing to take the drug for up to several days.
In contrast to cocaine, which is quickly removed from and almost completely metabolized in the body, methamphetamine has a much longer duration of action, and a larger percentage of the drug remains unchanged in the body. Methamphetamine therefore remains in the brain longer, which ultimately leads to prolonged stimulant effects.
Although both methamphetamine and cocaine increase levels of dopamine, administration of methamphetamine in animal studies leads to much higher levels of dopamine, because nerve cells respond differently to the two drugs. Cocaine prolongs dopamine actions in the brain by blocking the re-absorption (re-uptake) of the neurotransmitter by signaling nerve cells. At low doses, methamphetamine also blocks the re-uptake of dopamine, but it also increases the release of dopamine, leading to much higher concentrations in the synapse (the gap between neurons), which can be toxic to nerve terminals.
Some of the neurobiological effects of chronic methamphetamine misuse appear to be, at least, partially reversible. In the study just mentioned, abstinence from methamphetamine resulted in less excess microglial activation over time, and users who had remained methamphetamine-free for 2 years exhibited microglial activation levels similar to the study’s control subjects A similar study found that while biochemical markers for nerve damage and viability persist in the brain through 6 months of abstinence from methamphetamine, those markers return to normal after a year or more without taking the drug. Another neuroimaging study showed neuronal recovery in some brain regions following prolonged abstinence (14 but not 6 months). This recovery was associated with improved performance on motor and verbal memory tests.
Sources: NIH, National Institute on Drug Abuse, DEA, Wikipedia. (Collected 2023)