Methamphetamine is a highly addictive stimulant that affects the
central nervous system. Although most of the methamphetamine used in
this country comes from foreign or domestic superlabs, the drug is also
easily made in small clandestine laboratories, with relatively
inexpensive over-the-counter ingredients. These factors combine to make
methamphetamine a drug with high potential for widespread abuse.
Methamphetamine is commonly known as "speed," "meth," and "chalk." In its smoked form, it is often referred to as "ice," "crystal," "crank," and "glass." It is a white, odorless, bitter-tasting crystalline powder that easily dissolves in water or alcohol.
The drug was developed early last 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 general sense of well-being.
However, methamphetamine differs from amphetamine in that at comparable doses, much higher levels of methamphetamine get into the brain, making it a more potent stimulant drug. It also has longer lasting and more harmful effects on the central nervous system.
Methamphetamine is a Schedule II stimulant, which means it has a high
potential for abuse and is available only through a prescription. It is
indicated for the treatment of narcolepsy (a sleep disorder) and
attention deficit hyperactivity disorder; but these medical uses are
limited, and the doses are much lower than those typically abused.
Methamphetamine is commonly known as "speed," "meth," and "chalk." In its smoked form, it is often referred to as "ice," "crystal," "crank," and "glass." It is a white, odorless, bitter-tasting crystalline powder that easily dissolves in water or alcohol.
The drug was developed early last 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 general sense of well-being.
However, methamphetamine differs from amphetamine in that at comparable doses, much higher levels of methamphetamine get into the brain, making it a more potent stimulant drug. It also has longer lasting and more harmful effects on the central nervous system.
Methamphetamine
What is the scope of methamphetamine abuse in the United States?
NIDA's Community
Epidemiology Work Group (CEWG), an early warning network of researchers
that provides information about the nature and patterns of drug abuse in
21 major areas of the U.S., reported in January 2006 that
methamphetamine continues to be a problem in the West, with indicators
persisting at high levels in Honolulu, San Diego, Seattle, San
Francisco, and Los Angeles; and that it continues to spread to other
areas of the country, including both rural and urban sections of the
South and Midwest. In fact, methamphetamine was reported to be the
fastest growing problem in metropolitan Atlanta.
According to the 2005 National Survey on Drug Use and Health (NSDUH),
an estimated 10.4 million people age 12 or older (4.3 percent of the
population) have tried methamphetamine at some time in their lives.
Approximately 1.3 million reported past-year methamphetamine use, and 512,000 reported current (past-month) use.
Moreover, the 2005 Monitoring the Future (MTF) survey of student drug use and attitudes reported 4.5 percent of high school seniors had used methamphetamine within their lifetimes, while 8th-graders and 10th-graders reported lifetime use at 3.1 and 4.1 percent, respectively. However, neither of these surveys has documented an overall increase in the abuse of methamphetamine over the past few years. In fact, both surveys showed recent declines in methamphetamine abuse among the Nation's youth.
In contrast, evidence from emergency departments and treatment programs attest to the growing impact of methamphetamine abuse in the country.
The Drug Abuse Warning Network (DAWN), which collects information on drug-related episodes from hospital emergency departments (EDs) throughout the Nation, has reported a greater than 50 percent increase in the number of ED visits related to methamphetamine abuse between 1995 and 2002, reaching approximately 73,000 ED visits, or 4 percent of all drug-related visits in 2004.
Treatment admissions for methamphetamine abuse have also increased substantially. In 1992, there were approximately 21,000 treatment admissions in which methamphetamine/amphetamine was identified as the primary drug of abuse, representing more than 1 percent of all treatment admissions during the year. By 2004, the number of methamphetamine treatment admissions increased to greater than 150,000, representing 8 percent of all admissions.
Moreover, this increased involvement of methamphetamine in drug treatment admissions has also been spreading across the country. In 1992, only 5 states reported high rates of treatment admissions (i.e., >24 per 100,000 population) for primary methamphetamine/amphetamine problems; by 2002, this number increased to 21, more than a third of the states.
Primary Methamphetamine/Amphetamine Admission Rates per 100,000 Population Aged 12 and Over
Approximately 1.3 million reported past-year methamphetamine use, and 512,000 reported current (past-month) use.
Moreover, the 2005 Monitoring the Future (MTF) survey of student drug use and attitudes reported 4.5 percent of high school seniors had used methamphetamine within their lifetimes, while 8th-graders and 10th-graders reported lifetime use at 3.1 and 4.1 percent, respectively. However, neither of these surveys has documented an overall increase in the abuse of methamphetamine over the past few years. In fact, both surveys showed recent declines in methamphetamine abuse among the Nation's youth.
In contrast, evidence from emergency departments and treatment programs attest to the growing impact of methamphetamine abuse in the country.
The Drug Abuse Warning Network (DAWN), which collects information on drug-related episodes from hospital emergency departments (EDs) throughout the Nation, has reported a greater than 50 percent increase in the number of ED visits related to methamphetamine abuse between 1995 and 2002, reaching approximately 73,000 ED visits, or 4 percent of all drug-related visits in 2004.
Treatment admissions for methamphetamine abuse have also increased substantially. In 1992, there were approximately 21,000 treatment admissions in which methamphetamine/amphetamine was identified as the primary drug of abuse, representing more than 1 percent of all treatment admissions during the year. By 2004, the number of methamphetamine treatment admissions increased to greater than 150,000, representing 8 percent of all admissions.
Moreover, this increased involvement of methamphetamine in drug treatment admissions has also been spreading across the country. In 1992, only 5 states reported high rates of treatment admissions (i.e., >24 per 100,000 population) for primary methamphetamine/amphetamine problems; by 2002, this number increased to 21, more than a third of the states.
How is methamphetamine abused?
Methamphetamine comes in many forms and can be smoked, snorted,
injected, or orally ingested. The preferred method of methamphetamine
abuse varies by geographical region and has changed over time. Smoking
methamphetamine, which leads to very fast uptake of the drug in the
brain, has become more common in recent years, amplifying
methamphetamine's addiction potential and adverse health consequences.
The drug also alters mood in different ways, depending on how it is taken. Immediately after smoking the drug or injecting it intravenously, the user experiences an intense rush or "flash" that 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 similar stimulants, methamphetamine most often is used 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, abusers indulge in a form of binging known as a "run," foregoing food and sleep while continuing abuse for up to several days.
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 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.
This results in methamphetamine being present in the brain longer, which ultimately leads to prolonged stimulant effects.
And although both methamphetamine and cocaine increase levels of the brain chemical dopamine, animal studies reveal much higher levels of dopamine following administration of methamphetamine due to the different mechanisms of action within nerve cells in response to these drugs.
Cocaine prolongs dopamine actions in the brain by blocking dopamine re-uptake. While at low doses, methamphetamine blocks dopamine re-uptake, methamphetamine also increases the release of dopamine, leading to much higher concentrations in the synapse, which can be toxic to nerve terminals.
The drug also alters mood in different ways, depending on how it is taken. Immediately after smoking the drug or injecting it intravenously, the user experiences an intense rush or "flash" that 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 similar stimulants, methamphetamine most often is used 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, abusers indulge in a form of binging known as a "run," foregoing food and sleep while continuing abuse for up to several days.
How is methamphetamine different from other stimulants, such as cocaine?
Methamphetamine is structurally similar to amphetamine and the neurotransmitter dopamine, 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 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.
This results in methamphetamine being present in the brain longer, which ultimately leads to prolonged stimulant effects.
And although both methamphetamine and cocaine increase levels of the brain chemical dopamine, animal studies reveal much higher levels of dopamine following administration of methamphetamine due to the different mechanisms of action within nerve cells in response to these drugs.
Cocaine prolongs dopamine actions in the brain by blocking dopamine re-uptake. While at low doses, methamphetamine blocks dopamine re-uptake, methamphetamine also increases the release of dopamine, leading to much higher concentrations in the synapse, which can be toxic to nerve terminals.
What are the immediate (short-term) effects of methamphetamine abuse?
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.
Most of the pleasurable effects of methamphetamine are believed to
result from the release of very high levels of the neurotransmitter
dopamine.
Dopamine is involved in motivation, the experience of pleasure, and motor function, and is a common mechanism of action for most drugs of abuse.
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
Dopamine is involved in motivation, the experience of pleasure, and motor function, and is a common mechanism of action for most drugs of abuse.
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.
Dopamine Pathways:
In the brain, dopamine plays an important role in the regulation of
reward and movement.
As part of the reward pathway, dopamine is
manufactured in nerve cell bodies located within the ventral tegmental
area (VTA) and is released in the nucleus accumbens and the prefrontal
cortex.
Its motor functions are linked to a separate pathway, with cell
bodies in the substantia nigra that manufacture and release dopamine
into the striatum.
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