methamphetamine methamphetamine methamphetamine (contracted from n-methylamphetamine) is a potent central nervous system (cns) stimulant that is mainly used as a recreational drug and less commonly as a second-line treatment for attention deficit hyperactivity disorder and obesity. methamphetamine was discovered in 1893 and exists as two enantiomers: levo-methamphetamine and dextro-methamphetamine. methamphetamine properly refers to a specific chemical substance, the racemic free base, which is an equal mixture of levomethamphetamine and dextromethamphetamine in their pure amine forms. it is rarely prescribed over concerns involving human neurotoxicity and potential for recreational use as an aphrodisiac and euphoriant, among other concerns, as well as the availability of safer substitute drugs with comparable treatment efficacy such as adderall and vyvanse. dextroamphetamine is a stronger cns stimulant than levomethamphetamine. methamphetamine clinical datapronunciation/ˌmɛθæmˈfɛtəmiːn/(meth-am-fet-ə-meen), /ˌmɛθəmˈfɛtəmiːn/(meth-əm-fet-ə-meen), /ˌmɛθəmˈfɛtəmən/(meth-əm-fet-ə-mən) trade namesdesoxyn, methedrineother namesn-methylamphetamine, n,α-dimethylphenethylamine, desoxyephedrineahfs/drugs.commonographlicense data us fda: methamphetamine dependenceliabilityphysical: none; psychological: highaddictionliabilityhighroutes ofadministrationmedical: oral (ingestion)recreational: oral, intravenous, intramuscular, subcutaneous, vapour inhalation, insufflation, rectal, vaginalatc coden06ba03 (who) legal statuslegal status au: s8 (controlled drug) br: class a3 (psychoactive drugs) ca: schedule i de: anlage ii (authorized trade only, not prescriptible) nz: class a uk: class a us: schedule ii un: psychotropic schedule ii pharmacokinetic databioavailabilityoral: 67%intranasal: 79%inhalation: 67–90%intravenous: 100%protein bindingvaries widelymetabolismcyp2d6 and fmo3onset of actionoral: 3 hours (peak)intranasal: <15 minutesinhalation: <18 minutesintravenous: <15 minuteselimination half-life9–12 hours (range 5–30 hours) (irrespective of route)duration of action8–12 hoursexcretionprimarily kidneyidentifiers iupac name (rs)-n-methyl-1-phenylpropan-2-amine cas number537-46-2 y(dl)-methamphetamine hydrochloride: 300-42-5 ypubchem cid1206iuphar/bps4803drugbankdb01577 ychemspider1169 yunii44ral3456c(dl)-methamphetamine hydrochloride: 24gnz56d62 ykeggd08187 ychebichebi:6809 ychemblchembl1201201 ypdb ligandb40 (pdbe, rcsb pdb)comptox dashboard (epa)dtxsid8037128 echa infocard100.007.882 chemical and physical dataformulac10h15nmolar mass149.237 g·mol−13d model (jsmol)interactive imagechiralityracemic mixturemelting point170 °c (338 °f) boiling point212 °c (414 °f) at 760 mmhg smiles cnc(c)cc1ccccc1 inchi inchi=1s/c10h15n/c1-9(11-2)8-10-6-4-3-5-7-10/h3-7,9,11h,8h2,1-2h3 ykey:mywuzjcmwcohba-uhfffaoysa-n y (verify) both racemic methamphetamine and dextromethamphetamine are illicitly trafficked and sold owing to their potential for recreational use. the highest prevalence of illegal methamphetamine use occurs in parts of asia and oceania, and in the united states, where racemic methamphetamine and dextromethamphetamine are classified as schedule ii controlled substances. levomethamphetamine is available as an over-the-counter (otc) drug for use as an inhaled nasal decongestant in the united states. internationally, the production, distribution, sale, and possession of methamphetamine is restricted or banned in many countries, owing to its placement in schedule ii of the united nations convention on psychotropic substances treaty. while dextromethamphetamine is a more potent drug, racemic methamphetamine is illicitly produced more often, owing to the relative ease of synthesis and regulatory limits of chemical precursor availability. in low to moderate doses, methamphetamine can elevate mood, increase alertness, concentration and energy in fatigued individuals, reduce appetite, and promote weight loss. at very high doses, it can induce psychosis, breakdown of skeletal muscle, seizures and bleeding in the brain. chronic high-dose use can precipitate unpredictable and rapid mood swings, stimulant psychosis (e.g., paranoia, hallucinations, delirium, and delusions) and violent behavior. recreationally, methamphetamine's ability to increase energy has been reported to lift mood and increase sexual desire to such an extent that users are able to engage in sexual activity continuously for several days while binging the drug. methamphetamine is known to possess a high addiction liability (i.e., a high likelihood that long-term or high dose use will lead to compulsive drug use) and high dependence liability (i.e. a high likelihood that withdrawal symptoms will occur when methamphetamine use ceases). withdrawal from methamphetamine after heavy use may lead to a post-acute-withdrawal syndrome, which can persist for months beyond the typical withdrawal period. methamphetamine is neurotoxic to human midbrain dopaminergic neurons at high doses. methamphetamine has been shown to have a higher affinity and, as a result, higher toxicity toward serotonergic neurons than amphetamine. methamphetamine neurotoxicity causes adverse changes in brain structure and function, such as reductions in grey matter volume in several brain regions, as well as adverse changes in markers of metabolic integrity. methamphetamine belongs to the substituted phenethylamine and substituted amphetamine chemical classes. it is related to the other dimethylphenethylamines as a positional isomer of these compounds, which share the common chemical formula c10h15n. uses medical desoxyn (methamphetamine hydrochloride) 100 tablets in the united states, methamphetamine hydrochloride, under the trade name desoxyn, has been approved by the fda for treating adhd and obesity in both adults and children; however, the fda also indicates that the limited therapeutic usefulness of methamphetamine should be weighed against the inherent risks associated with its use. methamphetamine is sometimes prescribed off label for narcolepsy and idiopathic hypersomnia. in the united states, methamphetamine's levorotary form is available in some over-the-counter (otc) nasal decongestant products. as methamphetamine is associated with a high potential for misuse, the drug is regulated under the controlled substances act and is listed under schedule ii in the united states. methamphetamine hydrochloride dispensed in the united states is required to include a boxed warning regarding its potential for recreational misuse and addiction liability. desoxyn and desoxyn gradumet are both pharmaceutical forms of the drug. the latter is no longer produced and is a gradual-release form of the drug, flattening the curve of the effect of the drug while extending it. recreational