Methamphetamine Fact Card
- Methylamphetamine, Desoxyephedrine
- Synonyms for d-Methamphetamine:
- Synonyms for l-Methamphetamine:
- Synonyms for dl-Methamphetamine:
- Racemic Methamphetamine
- Brand Names:
- Desoxyn (d-Methamphetamine)
- Street Names:
- Meth, Tina, Crystal Meth, Ice, Glass, Crank
What is methamphetamine?
Methamphetamine, commonly known as meth, is a powerfully addictive CNS stimulant and anorectic — related to amphetamine in terms of chemistry and effects, though significantly more potent.  Prescription forms are available, but relatively uncommon. So unlike amphetamine, where most misuse occurs through diverted prescriptions, methamphetamine abuse is far more prevalent with illicit forms produced in underground meth labs. Methamphetamine is sought after primarily for its euphoric effects and its ability to delay sleep, sometimes for several days.
Methamphetamine is found in both prescription and illicitly manufactured forms. Prescription methamphetamine is found in the form of oral tablets and its active ingredient is d-methamphetamine — prescribed under generic labels and the brand Desoxyn for the treatment of ADHD and obesity.
Illicit methamphetamine is commonly found in powder and rock crystal forms. The powder form, also known as crank, can be smoked, snorted, or injected after liquefying. Crank tends to be cheaper and of lower purity than the crystal form, due to a tendency for street dealers to cut the powder with other substances in order to stretch profits. The crystal form, also known as ice or crystal meth, is consumed by smoking or injecting after liquefying.
Illicit methamphetamine is typically d-methamphetamine, though it can be dl-methamphetamine, depending on the chemical precursors used to synthesize the drug. 
What are d-methamphetamine, l-methamphetamine, and dl-methamphetamine?
Similar to amphetamine, the methamphetamine molecule exists in two basic forms, known as enantiomers (or isomers). They can be viewed simply as the right-handed and left-handed versions of the methamphetamine molecule: the d- (or dextro-) form and the l- (or levo-) form — d-methamphetamine and l-methamphetamine, respectively.
While the two molecules appear very similar, d-methamphetamine is far more potent and far more prone to abuse and addiction. l-Methamphetamine is shown to exhibit little, if any, of these effects. 
dl-Methamphetamine is a combination of equal amounts of d-methamphetamine and l-methamphetamine. dl-amphetamine is also known as racemic methamphetamine.
What are the effects of methamphetamine?
Methamphetamine is a potent CNS stimulant. Effects include a rush of energy and euphoria, rapid heartbeat, perspiration, jaw clenching, teeth grinding, and dilation of the pupils. Euphoric effects are thought to be provided by the release of the neurotransmitter dopamine. Users will typically remain awake as long as drug consumption continues. So methamphetamine episodes can last for several days.
Following large doses or during periods of methamphetamine-induced sleep deprivation, some users may display psychotic behaviors and symptoms. Known informally as meth psychosis, these behaviors may include agitation, delusions, paranoia, and auditory hallucinations. 
Methamphetamine is also a powerful anorectic. Users will generally avoid food while under its influence. This issue is especially problematic during long episodes of methamphetamine abuse. Significant weight loss is common among chronic meth users.
What are methamphetamine's long-term effects?
Long-term methamphetamine abuse can lead to a severe psychosis, which manifests in a number of possible behaviors, including anxiety, confusion, violence, extreme paranoia, and auditory hallucinations. Personal hygiene might be neglected, especially hygiene involving dental care — frequently resulting in a condition of oral disrepair known as meth mouth. Chronic users are also prone to severe weight loss brought about by poor nutrition and methamphetamine's potent anorectic effects. 
Urine Testing for Methamphetamine
Methamphetamine urine tests target d-methamphetamine, with possible cross-reactivity for l-methamphetamine and dl-methamphetamine. d-Methamphetamine is prominent in the urine of those ingesting d-methamphetamine or dl-methamphetamine (racemic methamphetamine), while l-methamphetamine is prominent in the urine of those ingesting l-methamphetamine or dl-methamphetamine (racemic methamphetamine). 
In a study published in the British Journal of Clinical Pharmacology, volunteers received intravenous doses of d-methamphetamine, l-methamphetamine, or dl-methamphetamine (1:1 racemic methamphetamine), and subsequently submitted to urinalysis screening. Approximately 44.9% and 43.2% of d-methamphetamine was recovered in the urine of the two groups receiving d-methamphetamine only. Approximately 55.7% and 49.1% of l-methamphetamine was recovered in the urine of the two groups receiving l-methamphetamine only. Approximately 38.3% of d-methamphetamine and approximately 52.4% l-methamphetamine were recovered in the urine of the those receiving dl-methamphetamine (1:1 racemic) only.