What is methamphetamine?

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 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, odourless, 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 originally used 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 behaviour.

Methamphetamine is a Schedule II stimulant, which means it has a high potential for abuse.

There are a few medical reasons for its use, such as treatment of narcolepsy, attention deficit disorder, and – for short term use – obesity, but these medical uses are limited.

How is methamphetamine used?

Methamphetamine comes in many forms and can be smoked, snorted, orally ingested, or injected. The drug 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 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 binging on the drug.

In the 1980´s, a smokable form of methamphetamine nicknamed “ice” came into use. Is 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.

Effects of methamphetamine on the brain

Dopamine plays an important role in the regulation of pleasure. In addition to other regions, dopamine is manufactured in nerve cells within the ventral tegmental area and is released in the nucleus accumbens and the frontal cortex. It appears that the drug stimulates excess release of dopamine, contributing to the effects on the user.

What are the immediate (short-term) effects of methamphetamine use?

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 snorting produces 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 pleasure.

The short-term effects of methamphetamine are:

·         Increased attention
·         Decreased fatigue
·         Increased activity
·         Decreased appetite
·         Euphoria and rush
·         Increased respiration
·         Hyperthermia

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.

What are the long-term effects of methamphetamine use?

Long-term methamphetamine abuse results in many damaging effects, including addiction. Addiction is a chronic, relapsing condition, characterized by compulsive drug-seeking and drug use 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 behaviour, 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 suicidal thoughts.

The long-term effects are:

·         Dependence
·         Addiction psychosis
·         Paranoia
·         Hallucination
·         Mood disturbances
·         Repetitive motor activity
·         Stroke 
·         Weight loss

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 binging known as a “run”, injecting as much as a gram of the drug every 2 or 3 hours over several days until the user runs out of the drug or is to disorganized to continue. Chronic abuse can lead to psychotic behaviour, characterized by intense paranoia, visual and auditory hallucinations, and out-of-control rages that can be coupled with extremely violent behaviour.

Although there are no physical manifestations of a withdrawal syndrome when methamphetamine use 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 the toxic effects on the brain. It is reported that as much as 50 % of the dopamine-producing cells in the brain can be damaged after prolonged exposure to relatively low levels of methamphetamine. Research has also demonstrated that serotonin-containing nerve cells may be damaged even more extensively.

What are the medical complications of methamphetamine use?

The drug 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. Hyperthermia (elevated body 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 behaviour, 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, as a common method of illegal methamphetamine production uses lead acetate as a reagent. Production errors may therefore result in methamphetamine contaminated with lead.

Fetal exposure to the drug also is a significant problem. At present, research indicates that methamphetamine abuse during pregnancy may result in prenatal complications, increased rates of premature delivery, and altered neonatal behavioural patters, such as abnormal reflexes and extreme irritability. Methamphetamine abuse during pregnancy may also be linked to congenital deformities.

How is methamphetamine different from other stimulants, like cocaine?

Methamphetamine is classified as a psychostimulant such as are other drugs of abuse as amphetamine and cocaine. Methamphetamine is structurally similar to amphetamine and the neurotransmitter dopamine, but it is quite different from cocaine. Although these stimulants have similar behavioural and physiological effects, there are some major differences in the basic mechanisms of how they work at the level of the nerve cell. However, the bottom line is that methamphetamine, like cocaine, results in an accumulation of the neurotransmitter dopamine, and this excessive dopamine concentration appears to produce the stimulation and feelings of euphoria experienced by the user.

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.