Methamphetamine - meth for short - is a very addictive stimulant drug. It is a powder that can be made into a pill or a shiny rock (called a crystal). The powder can be eaten or snorted up the nose. It can also be mixed with liquid and injected into your body with a needle. Crystal meth is smoked in a small glass pipe.

Meth at first causes a rush of good feelings, but then users feel edgy, overly excited, angry, or afraid. Meth use can quickly lead to addiction. It causes medical problems including

• Making your body temperature so high that you pass out
• Severe itching
• "Meth mouth" - broken teeth and dry mouth
• Thinking and emotional problems

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.

Methamphetamine was developed early in the 20th century from its parent drug, amphetamine, and was used originally in nasal decongestants and bronchial inhalers. Like amphetamine, methamphetamine causes increased activity and talkativeness, decreased appetite, and a pleasurable sense of well-being or euphoria. However, methamphetamine differs from amphetamine in that, at comparable doses, much greater amounts of the drug get into the brain, making it a more potent stimulant. It also has longer-lasting and more harmful effects on the central nervous system. These characteristics make it a drug with high potential for widespread misuse.

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.

Methamphetamine—meth for short—is a white, bitter powder. Sometimes it's made into a white pill or a clear or white shiny rock (called a crystal).

Smoking meth is the most common way it is used. Some mix the powder with liquid and inject it (shoot up) into their bodies with a needle. Others take the meth powder by mouth or snort it up the nose.

Meth causes a rush of good feelings at first. People who take it can then feel nervous, overly excited, angry, or afraid. Their thoughts and actions go really fast. They might feel too hot.

Some slang names for meth are:

• Crank
• Ice
• Crystal
• Glass
• Chalk

Signs of Meth Use

Meth speeds up breathing and raises blood pressure.

Meth can make people hyperactive—full of too much energy. They might talk and move around a lot. They might not stop to eat or sleep.

People who use meth often scratch their skin, causing sores. They might have burns on their lips or fingers from holding a hot meth pipe.

Meth can make a person's mood change quickly. For example, they might feel excited, and then become angry and violent. They might feel afraid that someone's out to get them. They might want to end their own life.

Effects of Meth on Brains and Bodies

These are just some of the problems meth can cause:

Overheating

Meth can make your body so hot that you pass out. Sometimes this can kill you.

Crank Bugs

Meth can make you feel like bugs are crawling on or under your skin. It makes you scratch a lot. Scratching causes sores on your face and arms.

Meth Mouth

People who use meth can break, stain, or rot their teeth. They often drink lots of sweet things, grind their teeth, and have dry mouth. This is called "meth mouth."

Looking Old

People who use meth can start looking old. They burn a lot of energy and don't eat well. This can make them lose weight and look sick. Their hands or body might shake. Their skin looks dull and has sores and pimples that don't heal. Their mouth looks sunken as the teeth go bad.

HIV/AIDS, Hepatitis

People who inject meth can get HIV/AIDS or hepatitis (a liver disease) if they share used needles. People also get these diseases by having unsafe sex. They often forget to use condoms because they're high on the drug.

Overdose

People can overdose on meth when they take too much of it. Sometimes drug dealers add other dangerous chemicals to meth that can help cause an overdose. They might get so hot that they pass out. If they don’t get help right away, they can die. A meth overdose can also cause a stroke (“brain attack”), heart attack, or liver failure. These can all cause death.

Addiction

You can become addicted to meth. Over time, it can change the way your brain works. If you stop using meth, your body can get confused and you can start to feel really sick. This makes it hard to stop. This is called addiction.

People who get addicted to meth start needing to take more of it to get the same high. People who usually snort meth or take it by mouth might start to smoke or inject it to get a stronger, quicker high.

Meth use can hurt different parts of your brain. It can cause thinking and emotional problems that don't go away. Even after you quit using meth, the thoughts can come back. For example, you might feel, hear, or see things that aren't there. You might think that people are out to get you or start believing strange ideas that can't really be true.

People who are trying to quit taking meth might:

• feel sad
• get really tired but have trouble sleeping
• feel angry or nervous
• be unable to feel happy

They will feel a very strong need to take the drug.

Fortunately, there is counseling that can help someone with a meth addiction.

Remember that even if you get treatment, it can be hard to stay off the drug. People who stopped using meth can still feel strong cravings for the drug, sometimes even years later. This is normal. This is also why it’s important to stay in treatment for as long as your doctor suggests.

All data refer to the United States population.

How many people use methamphetamine?

• Among people aged 12 or older in 2020, 0.9% (or about 2.6 million people) reported using methamphetamine in the past 12 months.
  Source: 2020 National Survey on Drug Use and Health

How many young students use methamphetamine?

• In 2021, an estimated 0.2% of 8 graders, 0.2% of 10 graders, and 0.2% of 12 graders reported using methamphetamine in the past 12 months.
  Source: 2021 Monitoring the Future Survey

How many people have a methamphetamine use disorder?

• Among people aged 12 or older in 2020, an estimated 0.6% (or about 1.5 million people) had a methamphetamine use disorder in the past 12 months.
  Source: 2020 National Survey on Drug Use and Health

How many people die from methamphetamine overdose?

• In 2020, approximately 23,837 people died from an overdose involving psychostimulants with abuse potential other than cocaine (primarily methamphetamine). Learn more about overdose death rates.
  Source: CDC WONDER Database

Methamphetamine comes in several forms and can be smoked, snorted, injected, or orally ingested. The preferred method of using the drug varies by geographical region and has changed over time.

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.

Currently, most methamphetamine in the United States is produced by transnational criminal organizations (TCOs) in Mexico. This methamphetamine is highly pure, potent, and low in price. The drug can be easily made in small clandestine laboratories, with relatively inexpensive over-the-counter ingredients such as pseudoephedrine, a common ingredient in cold medications.

To curb production of methamphetamine, Congress passed the Combat Methamphetamine Epidemic Act in 2005, which requires that pharmacies and other retail stores keep logs of purchases of products containing pseudoephedrine and limits the amount of those products an individual can purchase per day. Restrictions on the chemicals used to make methamphetamine in the United States have dramatically reduced domestic production of the drug. In 2010, there were 15,256 domestic methamphetamine laboratory incidents—a figure that has fallen over 80 percent to 3,036 in 2017. Data on drug seizures indicate that most domestic production of methamphetamine is now conducted in small laboratories that make two ounces or less of the drug using common household items.

Mexico has also tightened its restrictions on pseudoephedrine and other methamphetamine precursor chemicals. But manufacturers adapt to these restrictions via small- or large-scale "smurfing" operations: obtaining pseudoephedrine from multiple sources, below the legal thresholds, using multiple false identifications. Manufacturers in Mexico are also increasingly using a different production process (called P2P which stands for pseudoephedrine’s precursor chemical, phenyl-2-propanone) to make methamphetamine that does not require pseudoephedrine.

When methamphetamine is smuggled into the United States in powder or liquid form, domestic conversion laboratories transform it into crystal methamphetamine. These laboratories do not require a significant amount of equipment, so they can be small in size and thus easily concealed, which presents challenges to law enforcement agencies. Methamphetamine pressed into a pill form intended to resemble ecstasy has also recently emerged, potentially in an effort to make methamphetamine more appealing to people who haven’t tried it before. As with other illicit drugs like heroin and cocaine, methamphetamine is also sometimes laced with fentanyl.

Methamphetamine production is also an environmental concern; it involves many easily obtained chemicals that are hazardous, such as acetone, anhydrous ammonia (fertilizer), ether, red phosphorus, and lithium. Toxicity from these chemicals can remain in the environment around a methamphetamine production lab long after the lab has been shut down, causing a wide range of damaging effects to health. Because of these dangers, the U.S. Environmental Protection Agency has provided guidance on cleanup and remediation of methamphetamine labs.

The methamphetamine molecule is structurally similar to amphetamine and to the neurotransmitter dopamine, a brain chemical that plays an important role in the reinforcement of rewarding behaviors, but it is quite different from cocaine. Although these stimulants have similar behavioral and physiological effects, there are some major differences in the basic mechanisms of how they work.

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.

Methamphetamine versus Cocaine

As a powerful stimulant, methamphetamine, even in small doses, can increase wakefulness and physical activity and decrease appetite. Methamphetamine can also cause a variety of cardiovascular problems, including rapid heart rate, irregular heartbeat, and increased blood pressure. Hyperthermia (elevated body temperature) and convulsions may occur with methamphetamine overdose, and if not treated immediately, can result in death.

The exact mechanisms whereby drugs like methamphetamine produce euphoria (the pleasurable high) are still poorly understood. But along with euphoria, methamphetamine use releases very high levels of the neurotransmitter dopamine in the reward circuit, which "teaches" the brain to repeat the pleasurable activity of taking the drug. Dopamine is involved in motivation and motor function and its release in the reward circuit is a defining feature of addictive drugs. The elevated release of dopamine produced by methamphetamine is also thought to contribute to the drug's deleterious effects on nerve terminals in the brain.

Short-term effects may include:

• increased attention and decreased fatigue
• increased activity and wakefulness
• decreased appetite
• euphoria and rush
• increased respiration
• rapid/irregular heartbeat
• hyperthermia

Long-term methamphetamine abuse has many negative consequences, including addiction. Addiction is a chronic, relapsing disease, characterized by compulsive drug seeking and use and accompanied by functional and molecular changes in the brain.

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.

These and other problems reflect significant changes in the brain caused by misuse of methamphetamine. 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. 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.

Methamphetamine misuse also has been shown to have negative effects on non-neural brain cells called microglia. These cells support brain health by defending the brain against infectious agents and removing damaged neurons. Too much activity of the microglial cells, however, can assault healthy neurons. A study using brain imaging found more than double the levels of microglial cells in people who previously misused methamphetamine compared to people with no history of methamphetamine misuse, which could explain some of the neurotoxic effects of methamphetamine.

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. 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.

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.

Long-term effects may include:

• addiction
• psychosis, including:
  • paranoia
  • hallucinations
  • repetitive motor activity
• changes in brain structure and function
• deficits in thinking and motor skills
• increased distractibility
• memory loss
• aggressive or violent behavior
• mood disturbances
• severe dental problems
• weight loss

Our knowledge of the effects of methamphetamine misuse during pregnancy is limited because studies of this issue have used small samples and did not account for other possible drug use besides methamphetamine in research samples. But the available research indicates increased rates of premature delivery, placental abruption (separation of the placental lining from the uterus), and various effects on babies prenatally exposed to methamphetamine, including small size, lethargy, and heart and brain abnormalities.

A large NIDA-funded prospective, longitudinal study examined developmental outcomes in infants and children born to mothers who misused methamphetamine. In infancy, they were more likely to show decreased arousal, increased stress, and poor quality of movement. By ages 1 and 2, toddlers showed delayed motor development. Preschool and school-age children had subtle but significant attention impairments and were more likely to have cognitive and behavioral issues in school related to difficulties with self-control and executive function.

Methamphetamine misuse raises the risk of contracting or transmitting HIV and hepatitis B and C—not only for individuals who inject the drug but also for noninjecting methamphetamine users. Among people who inject drugs, HIV and other infectious diseases are spread primarily through the re-use or sharing of contaminated syringes, needles, or related paraphernalia. But regardless of how methamphetamine is taken, its strong effects can alter judgment and inhibition and lead people to engage in risky behaviors like unprotected sex.

Methamphetamine misuse is associated with a culture of risky sexual behavior, both among men who have sex with men and in heterosexual populations, a link that may be attributed to the fact that methamphetamine and related stimulants can increase libido. (However, long-term methamphetamine misuse may be associated with decreased sexual functioning, at least in men.) The combination of injection practices and sexual risk-taking may result in HIV becoming a greater problem among people who misuse methamphetamine than among other drug users, and some epidemiologic reports are already showing this trend. For example, while the link between HIV infection and methamphetamine misuse has not yet been established for heterosexuals, data show an association between methamphetamine misuse and the spread of HIV among men who have sex with men.

Methamphetamine misuse may also worsen the progression of HIV disease and its consequences. In animal studies, methamphetamine has been shown to increase viral replication. Clinical studies in humans suggest that current methamphetamine users taking highly active antiretroviral therapy (HAART) to treat HIV may be at greater risk of developing AIDS than non-users, possibly because of poor medication adherence. Methamphetamine users with HIV also have shown greater neuronal injury and cognitive impairment due to HIV, compared with those who do not misuse the drug.

NIDA-funded research has found that, through substance use disorder treatment, prevention, and community-based outreach programs, drug users can change their HIV risk behaviors. Drug misuse and drug-related risk behaviors, such as needle sharing and risky sexual practices, can be reduced significantly, thus decreasing the risk of exposure to HIV and other infectious diseases. Therefore, drug treatment is HIV prevention.

Dopamine Pathways

In the brain, dopamine plays an important role in both movement and the reinforcement of rewarding behaviors. As a major chemical messenger in the reward pathway, dopamine is manufactured in nerve cell bodies located within a group of neurons called the ventral tegmental area and is released in the nucleus accumbens, which is a key brain region for learning to repeat pleasurable activities, as well as in the prefrontal cortex, which is responsible for higher cognitive functions like decision-making and self-control. Dopamine’s regulation of motor functions is linked to a separate pathway: Cell bodies in the substantia nigra manufacture and release dopamine into the striatum, which is involved in executing and inhibiting movements and reward-seeking behavior.

The most effective treatments for methamphetamine addiction at this point are behavioral therapies, such as cognitive-behavioral and contingency management interventions. For example, the Matrix Model—a 16-week comprehensive behavioral treatment approach that combines behavioral therapy, family education, individual counseling, 12-step support, drug testing, and encouragement for non-drug-related activities—has been shown to be effective in reducing methamphetamine misuse. Contingency management interventions, which provide tangible incentives in exchange for engaging in treatment and maintaining abstinence, have also been shown to be effective.

Although medications have proven effective in treating some substance use disorders, there are currently no medications that counteract the specific effects of methamphetamine or that prolong abstinence from and reduce the misuse of methamphetamine by an individual addicted to the drug.

Pharmacological Treatments

There are currently no medications that counteract the specific effects of methamphetamine or that prolong abstinence from and reduce the use of methamphetamine by an individual addicted to the drug. NIDA has made research on the development of medications to treat addiction to stimulants and other drugs a priority, and NIDA-funded researchers are investigating a number of pharmacological approaches for treating methamphetamine use disorder.

When developing drug treatments, researchers typically examine the impact of potential medications that have neurobiological effects that may counter the known physiological consequences of chronic methamphetamine use. They may also test medications that have shown promise in treating other addictions or other psychiatric disorders. The following targets and strategies have shown promise in animal or human studies related to methamphetamine use disorder:

The neuroimmune system: Chronic methamphetamine use is associated with activation of microglia, cells that mediate inflammation in the central nervous system. Drugs like ibudilast and minocycline are being studied for their capacity to inhibit activation of microglia.

Cognitive enhancement: Chronic methamphetamine use is also associated with cognitive problems, such as impaired decision-making and impaired behavioral inhibition. Several drugs are under investigation for their potential to improve cognition in people who use methamphetamine.

Dopamine agonist treatment: Medications based on activation of the same receptors targeted by an addictive drug are effective in treating other addictions, such as the use of methadone or buprenorphine to treat opioid use disorder and the use of nicotine replacement to assist smoking cessation. Since methamphetamine targets the dopamine system, some stimulant medications that activate dopamine receptors (agonists) and that are often used to treat attention-deficit hyperactivity disorder (ADHD) are being investigated as potential medications to treat methamphetamine use disorder.

Other monoamine (serotonin, norepinephrine, dopamine) targets: Methamphetamine withdrawal symptoms are similar to depression, leading researchers to investigate the utility of antidepressants that act on the serotonin and norepinephrine systems for methamphetamine use disorder. Antipsychotic medications also act on the dopamine system and may have promise for ameliorating the effects of chronic methamphetamine use.

The opioid system: The euphoric effects of addictive drugs likely involve the opioid system. Candidate medications in this category include the opioid antagonist naltrexone (currently being studied in combination with the antidepressant bupropion) and the opioid partial agonist buprenorphine.

GABA and glutamate systems: Several medications targeting disruptions in the balance of excitation and inhibition (mediated by the neurotransmitters GABA and glutamate) are being investigated to treat methamphetamine use disorder.

Hormones: The hormones cholecystokinin-8 and oxytocin have both shown promise in reducing the rewarding properties of methamphetamine in animals.

Nonpharmacological Treatments

Nonpharmacological treatments do not involve use of medications. Such therapies may instill behavioral changes by altering brain activity patterns (TMS), helping people learn how to monitor and control brain activity to curb symptoms of addiction (neurofeedback), or keeping drugs out of the brain (vaccines). Although further research is needed on these approaches, they may provide additional options for treatment providers and patients.

Transcranial Magnetic Stimulation: TMS is a noninvasive method of stimulating the brain using magnetic pulses for therapeutic purposes. Researchers are studying this approach as a treatment for substance use disorders, but this work is in very early stages.

Neurofeedback: Neurofeedback (also called neurotherapy or neurobiofeedback) is a type of biofeedback that uses real-time displays of brain activity—most commonly electroencephalography—to teach people how to regulate their own brain function. In one study, neurofeedback to treatment for methamphetamine use disorder reduced addiction severity and improved mental health and overall quality of life.

Vaccines and antibodies: Methamphetamine vaccines, which recruit the body’s immune system to keep the drug from entering the brain, are currently being tested in animals, and a human clinical trial is currently underway to test an immunologic agent called a monoclonal antibody, which binds to methamphetamine and neutralizes it before it can exert its effects.

What is methamphetamine?

Methamphetamine is a powerful, highly addictive stimulant that affects the central nervous system. Crystal methamphetamine is a form of the drug that looks like glass fragments or shiny, bluish-white rocks. It is chemically similar to amphetamine, a drug used to treat attention-deficit hyperactivity disorder (ADHD) and narcolepsy, a sleep disorder.

How do people use methamphetamine?

People can take methamphetamine by:

• smoking
• swallowing (pill)
• snorting
• injecting the powder that has been dissolved in water/alcohol

Because the "high" from the drug both starts and fades quickly, people often take repeated doses in a "binge and crash" pattern. In some cases, people take methamphetamine in a form of binging known as a "run," giving up food and sleep while continuing to take the drug every few hours for up to several days.

How does methamphetamine affect the brain?

Methamphetamine increases the amount of the natural chemical dopamine in the brain. Dopamine is involved in body movement, motivation, and reinforcement of rewarding behaviors. The drug’s ability to rapidly release high levels of dopamine in reward areas of the brain strongly reinforces drug-taking behavior, making the user want to repeat the experience.

Short-Term Effects

Taking even small amounts of methamphetamine can result in many of the same health effects as those of other stimulants, such as cocaine or amphetamines. These include:

• increased wakefulness and physical activity
• decreased appetite
• faster breathing
• rapid and/or irregular heartbeat
• increased blood pressure and body temperature

How Do Manufacturers Make Methamphetamine?

Currently, most methamphetamine in the United States is produced by transactional criminal organizations (TCOs) in Mexico. This methamphetamine is highly pure, potent, and low in price. The drug can be easily made in small clandestine laboratories, with relatively inexpensive over-the-counter ingredients such as pseudoephedrine, a common ingredient in cold medications. To curb this kind of production, the law requires pharmacies and other retail stores to keep a purchase record of products containing pseudoephedrine, and take steps to limit sales.

Methamphetamine production also involves a number of other very dangerous chemicals. Toxic effects from these chemicals can remain in the environment long after the lab has been shut down, causing a wide range of health problems for people living in the area. These chemicals can also result in deadly lab explosions and house fires.

What are other health effects of methamphetamine?

Long-Term Effects

People who inject methamphetamine are at increased risk of contracting infectious diseases such as HIV and hepatitis B and C. These diseases are transmitted through contact with blood or other bodily fluids that can remain on drug equipment. Methamphetamine use can also alter judgment and decision-making leading to risky behaviors, such as unprotected sex, which also increases risk for infection.

Methamphetamine use may worsen the progression of HIV/AIDS and its consequences. Studies indicate that HIV causes more injury to nerve cells and more cognitive problems in people who use methamphetamine than it does in people who have HIV and don't use the drug. Cognitive problems are those involved with thinking, understanding, learning, and remembering.

Long-term methamphetamine use has many other negative consequences, including:

• extreme weight loss
• addiction
• severe dental problems
• intense itching, leading to skin sores from scratching
• anxiety
• changes in brain structure and function
• confusion
• memory loss
• sleeping problems
• violent behavior
• paranoia—extreme and unreasonable distrust of others
• hallucinations—sensations and images that seem real though they aren't

In addition, continued methamphetamine use causes changes in the brain's dopamine system that are associated with reduced coordination and impaired verbal learning. In studies of people who used methamphetamine over the long term, severe changes also affected areas of the brain involved with emotion and memory. This may explain many of the emotional and cognitive problems seen in those who use methamphetamine.

Although some of these brain changes may reverse after being off the drug for a year or more, other changes may not recover even after a long period of time. A recent study even suggests that people who once used methamphetamine have an increased the risk of developing Parkinson's disease, a disorder of the nerves that affects movement.

Are there health effects from exposure to secondhand methamphetamine smoke?

Researchers don't yet know whether people breathing in secondhand methamphetamine smoke can get high or have other health effects. What they do know is that people can test positive for methamphetamine after exposure to secondhand smoke. More research is needed in this area.

Can a person overdose on methamphetamine?

Yes, a person can overdose on methamphetamine. An overdose occurs when the person uses too much of a drug and has a toxic reaction that results in serious, harmful symptoms or death.

In 2017, about 15 percent of all drug overdose deaths involved the methamphetamine category, and 50 percent of those deaths also involved an opioid, with half of those cases related to the synthetic opioid fentanyl. (CDC Wonder Multiple Causes of Death—see #42 on Meth RR.) It is important to note that cheap, dangerous synthetic opioids are sometimes added to street methamphetamine without the user knowing

How can a methamphetamine overdose be treated?

Because methamphetamine overdose often leads to a stroke, heart attack, or organ problems, first responders and emergency room doctors try to treat the overdose by treating these conditions, with the intent of:

• restoring blood flow to the affected part of the brain (stroke)
• restoring blood flow to the heart (heart attack)
• treating the organ problems

Is methamphetamine addictive?

Yes, methamphetamine is highly addictive. When people stop taking it, withdrawal symptoms can include:

• anxiety
• fatigue
• severe depression
• psychosis
• intense drug cravings

How is methamphetamine addiction treated?

While research is underway, there are currently no government-approved medications to treat methamphetamine addiction. The good news is that methamphetamine misuse can be prevented and addiction to the drug can be treated with behavioral therapies. The most effective treatments for methamphetamine addiction so far are behavioral therapies, such as:

• cognitive-behavioral therapy, which helps patients recognize, avoid, and cope with the situations likely to trigger drug use.
• motivational incentives, which uses vouchers or small cash rewards to encourage patients to remain drug-free

Research also continues toward development of medicines and other new treatments for methamphetamine use, including vaccines, and noninvasive stimulation of the brain using magnetic fields. People can and do recover from methamphetamine addiction if they have ready access to effective treatments that address the multitude of medical and personal problems resulting from long-term use.

Points to Remember

• Methamphetamine is usually a white, bitter-tasting powder or a pill. Crystal methamphetamine looks like glass fragments or shiny, bluish-white rocks.
• Methamphetamine is a stimulant drug that is chemically similar to amphetamine (a drug used to treat ADHD and narcolepsy).
• People can take methamphetamine by smoking, swallowing, snorting, or injecting the drug.
• Methamphetamine increases the amount of dopamine in the brain, which is involved in movement, motivation, and reinforcement of rewarding behaviors.
• Short-term health effects include increased wakefulness and physical activity, decreased appetite, and increased blood pressure and body temperature.
• Long-term health effects include risk of addiction; risk of contracting HIV and hepatitis; severe dental problems; intense itching, leading to skin sores from scratching; violent behavior; and paranoia.
• Methamphetamine can be highly addictive. When people stop taking it, withdrawal symptoms can include anxiety, fatigue, severe depression, psychosis, and intense drug cravings.
• Researchers don't yet know if people breathing in secondhand methamphetamine smoke can get high or suffer other health effects.
• A person can overdose on methamphetamine. Because methamphetamine overdose often leads to a stroke, heart attack, or organ problems, first responders and emergency room doctors try to treat the overdose by treating these conditions.
• The most effective treatments for methamphetamine addiction so far are behavioral therapies. There are currently no government-approved medications to treat methamphetamine addiction.