Developed by the Japanese chemist A. Ogata in 1919, methamphetamine (meth) was used during World War II to help soldiers stay alert and to energize factory workers. After World War II a massive supply of meth, formerly stocked by the Japanese military, became available in Japan; skyrocketing addiction.

Amphetamines first came to this country at the start of the 1930s, and abuse of amphetamine sulfate (Benzedrine) and dextroamphetamine (Dexedrine) pills became widespread during the 1950s and 60s. These pills were commonly prescribed by physicians, most often for weight loss, and massively diverted to the illicit market. Meth was also traded on the street, mostly as a powder that could be snorted or made into an injectable solution.

Injection of amphetamines dates from the 1960s, when some users began shooting the drug into their veins to achieve a more intense “high.” High-intensity users (known as speed freaks) would often inject amphetamine for days, until overcome by exhaustion or psychosis. The aggressive behavior of these users, their volatile temper, physical depletion, and profound weight loss gave rise to the once–familiar warning that “speed kills.”

By the end of the 60s, amphetamine abuse began to wane. Illicit sales dwindled after the federal government tightened controls on amphetamine production in 1970, and the Drug Enforcement Administration and medical licensing boards cracked down on “script doctors” who freely handed out amphetamine prescriptions.

In the 1980s, ice, a extremely addictive and potent form of meth, came into use.

In the United States, there have been three distinct meth epidemics: one in the 1950s, a second in the late 1960s, and the third and current one that began in the mid-1990s.

Physical Effects

Like other amphetamines, meth induces a temporary state of alertness, increased energy, suppressed appetite, and feelings of well-being. Continued use may result in sever anxiety, sleeplessness, and a paranoid psychosis. Chronic abuse overtakes the body, resulting in malnutrition and increased susceptibility to disease. Users can become physically and psychologically dependent on meth. Overdose leading to death can occur.

With low to moderate doses, users may experience enhanced talkativeness, dizziness, headaches, palpitations, and tremors.

Meth is reported to attack the immune system, so users are often prone to infections of all different kinds, one being MRSA—a potentially deadly infection of Staph bacteria resistant to conventional antibiotics. This, too, may simply be a result of long-term sleep deprivation and/or chronic malnutrition.

It’s a common belief that meth gives people super-human strength. This of course is false, but meth inhibits pain and increases metabolism, allowing the user to push muscles to points of failure that would otherwise be harder or impossible to reach.

Other side effects include twitching, jitteriness, repetitive behavior (known as tweaking), and jaw clenching or teeth grinding. It has been noted that meth addicts lose their teeth abnormally fast due to a combination of side effects, although heavy users also tend to neglect personal hygiene, such as brushing teeth.

Some users exhibit sexually compulsive behavior and may engage in extended sexual encounters with one or more individuals, often strangers. This behavior is substantially more common among gay and bisexual male meth users than their heterosexual counterparts. As it’s symptomatic of the user to continue taking the drug to combat fatigue, it’s an encounter or series of encounters can last for several days. This compulsive behavior has created a link between meth use and sexually transmitted disease (STD) transmission, especially HIV and syphilis.

In scientific studies examining the consequences of long-term meth exposure, concern has arisen over its toxic effects on the brain. Researchers report that as much as 50% of the dopamine-producing cells in the brain can be damaged after prolonged exposure to relatively low levels of meth. Serotonin-containing nerve cells may be damaged even more extensively. Whether this toxicity is related to the psychosis seen in some long-term meth abusers is still an open question. Over time, meth appears to cause reduced levels of dopamine, which can result in symptoms similar to those of Parkinson’s disease, a severe movement disorder.

Animal research shows that high doses of meth damage neuron cell endings. Dopamine- and serotonin-containing neurons do not die after meth use, but their nerve endings (terminals) are cut back, and regrowth appears to be limited.

Eroding the Mind
In this brain scan of a meth abuser, the areas in red show the highest damage, with the blue shades marking areas with the least.

click image to enlarge

The central nervous system (CNS) actions that result from taking even small amounts of meth include increased wakefulness, increased physical activity, decreased appetite, increased respiration, hypothermia, and euphoria. Other CNS effects include irritability, insomnia, confusion, tremors, convulsions, anxiety, paranoia, and aggressiveness. Hypothermia and convulsions can result in death.

Brain damage from chronic meth abuse is equal or greater than the gray matter deficits found in patients with dementia or schizophrenia. A recent study from the Univ. of California at Los Angeles shows that meth abusers had 11% less gray matter than the non-abuser.

When injected into the blood stream, meth travels directly to the heart causing a high feeling within about 30 seconds. Physical effects can include constriction of veins and arteries which reduces blood flow and increases blood pressure, increased body temperature, faster heartbeat, and possible blood clotting.

Other dangers of use include risk of arrhythmia (heart out of rhythm), heart attacks, and cardiovascular collapse—all potentially deadly effects.

The ingredients used to make meth can actually block the lungs blood vessels. Long term use can permanently reduce the amount of air the lungs are able to take in.
Using meth slows down the digestive tract as well as the breakdown of food. This results in feeling less hungry and thirsty. Dangers include extreme anorexia, constipation, diarrhea, dehydration, malnutrition, and cramping.
The liver breaks down meth into simpler components. The liver however, cannot break down large amounts of toxic substances at the same time. Meth competes with other poisons in the body awaiting removal. When this happens, toxic substances are allowed into the blood stream which can cause dangerous drug interactions and overdose. Dangers include heart attack, stroke, coma, and/or death.


The kidneys filter blood by excreting liquid waste. Meth constricts the blood vessels of the kidneys so that less urine is excreted. As a result, toxic wastes are allowed back into the body. Toxic blood in the brain can cause headaches and mental confusion. Long term use may cause bladder infections and inflamed kidneys.
Dry mouth is frequently experienced when taking meth. This is a physical effect where less saliva and more acid is produced in the mouth. These acids can cause meth mouth, characterized by severe tooth decay, gum disease, bone and tooth loss.


The Faces of Addiction

The downward spiral due to meth addiction as seen through jail booking photos.
A frequent face in the New York City jail, this college graduate now has a resume
full of Prostitution, Possession, and Drug Dealing Convictions.


NIDA Infofacts: Methamphetamine, National Institute on Drug Abuse, May 2005
Thompson PM, Hayashi KM, Simon SL, et al. (June 2004) Structual abnormalities in the brains of human subjects who use methamphetamine. The Journal of Neuroscience 24(26): 6028-6036.