Methamphetamine is a powerfully addictive stimulant that dramatically affects the
central nervous system. The drug is made easily in clandestine laboratories with
relatively inexpensive over-the-counter ingredients. These factors combine to make
meth-amphetamine 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 in this century from its parent drug, amphetamine, and
was used originally in nasal decongestants and bronchial inhalers. Methamphetamine's
chemical structure is similar to that of amphetamine, but it has more pronounced effects
on the central nervous system. Like amphetamine, it causes increased activity,
decreased appetite, and a general sense of well-being. The effects of methamphetamine can
last 6 to 8 hours. After the initial "rush," there is typically a
state of high agitation that in some individuals can lead to violent behavior.
Methamphetamine is a Schedule II stimulant, which means it has a high potential for
abuse and is available only through a prescription that cannot be refilled. There
are a few accepted medical reasons for its use, such as the treatment of narcolepsy,
attention deficit disorder, and for short-term use obesity; but these medical uses
Methamphetamine comes in many forms and can be smoked, snorted, orally ingested, or
injected. The drug alters moods 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 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 tolerance for methamphetamine occurs within minutes --
meaning that the pleasurable effects disappear even before the drug concentration in the
blood falls significantly. Users try to maintain the high by bingeing on the drug.
In the 1980's, "ice," a smokable form of methamphetamine, came into use. Ice
is a large, usually clear crystal of high purity that is smoked in a glass pipe like crack
cocaine. The smoke is odorless, leaves a residue that can be resmoked, and produces
effects that may continue for 12 hours or more.
- Increased attention and decreased fatigue
- Increased activity
- Decreased appetite
- Euphoria and rush
- Increased respiration
As a powerful stimulant, methamphetamine, even in small doses, can increase wakefulness
and physical activity and decrease appetite. A brief, intense sensation, or rush, is
reported by those who smoke or inject methamphetamine. Oral ingestion or
a long-lasting high instead of a rush, which reportedly can continue for as long as half a
day. Both the rush and the high are believed to result from the release of very high
levels of the neurotransmitter dopamine into areas of the brain that regulate feelings of
Methamphetamine has toxic effects. In animals, a single high dose of the drug has been
shown to damage nerve terminals in the dopamine-containing regions of the brain. The large
release of dopamine produced by methamphetamine is thought to contribute to the drug's
toxic effects on nerve terminals in the brain. High doses can elevate body temperature to
dangerous, sometimes lethal, levels, as well as cause convulsions.
- Dependence and addiction psychosis
- mood disturbances
- repetitive motor activity
- Weight loss
- Dental destruction
Long-term methamphetamine abuse results in many damaging effects, including addiction.
Addiction is a chronic, relapsing disease, characterized by compulsive drug-seeking and
drug use which is accompanied by functional and molecular changes in the brain. In
addition to being addicted to methamphetamine, chronic methamphetamine abusers exhibit
symptoms that can include violent behavior, anxiety, confusion, and insomnia. They also
can display a number of psychotic features, including paranoia, auditory hallucinations,
mood disturbances, and delusions (for example, the sensation of insects creeping on the
skin, called "formication"). The paranoia can result in homicidal as well as
With chronic use, tolerance for methamphetamine can develop. In an
effort to intensify the desired effects, users may take higher doses of the drug, take it
more frequently, or change their method of drug intake. In some cases, abusers forego food
and sleep while indulging in a form of bingeing known as a "run," injecting as
much as a gram of the drug every 2 to 3 hours over several days until the user runs out of
the drug or is too disorganized to continue. Chronic abuse can lead to psychotic behavior,
characterized by intense paranoia, visual and auditory hallucinations, and out-of-control
rages that can be coupled with extremely violent behavior.
Although there are no physical manifestations of a withdrawal syndrome when
methamphetamine use is stopped, there are several symptoms that occur when a chronic user
stops taking the drug. These include depression, anxiety, fatigue, paranoia, aggression,
and an intense craving for the drug.
In scientific studies examining the consequences of long-term methamphetamine exposure
in animals, concern has arisen over its toxic effects on the brain. Researchers have
reported that as much as 50 percent of the dopamine-producing cells in the brain can be
damaged after prolonged exposure to relatively low levels of methamphetamine. Researchers
also have found that serotonin-containing nerve cells may be damaged even more
extensively. Whether this toxicity is related to the psychosis seen in some long-term
methamphetamine abusers is still an open question.
Methamphetamine can cause a variety of cardiovascular problems. These include rapid
heart rate, irregular heartbeat, increased blood pressure, and irreversible,
stroke-producing damage to small blood vessels in the brain. Hypothermia (decreased
temperature) and convulsions occur with methamphetamine overdoses, and if not treated
immediately, can result in death.
Chronic methamphetamine abuse can result in inflammation of the heart lining, and among
users who inject the drug, damaged blood vessels and skin abscesses. Methamphetamine
abusers also can have episodes of violent behavior, paranoia, anxiety, confusion, and
insomnia. Heavy users also show progressive social and occupational deterioration.
Psychotic symptoms can sometimes persist for months or years after use has ceased.
Acute lead poisoning is another potential risk for methamphetamine abusers. A common
method of illegal methamphetamine production uses lead acetate as a reagent. Production
errors may therefore result in methamphetamine contaminated with lead. There have been
documented cases of acute lead poisoning in intravenous methamphetamine abusers.
Fetal exposure to methamphetamine also is a significant problem in the United States.
At present, research indicates that methamphetamine abuse during pregnancy may result in
prenatal complications, increased rates of premature delivery, and altered neonatal
behavioral patterns, such as abnormal reflexes and extreme irritability. Methamphetamine
abuse during pregnancy may be linked also to congenital deformities.
|Source: NIDA Research Report - Methamphetamine Abuse and Addiction: NIH
Publication No. 98-4210 Printed April, 1998