药品详情：
【诺罗丁Desoxyn 简述】
Desoxyn是d-甲基安非他命（右旋甲基苯丙胺）的药品商标。
【诺罗丁Desoxyn 适应症】
诺罗丁Desoxyn在医疗上可用于治疗注意力不足过动症(ADHD)、嗜睡症以及极端的肥胖症等，但不带甲基的安非他命更常用。当安非他命和甲基安非他命致使患者太多副作用时，Desoxyn作为次选药物。
【诺罗丁Desoxyn 规格】
本品为片剂，每片含有效成份5mg，每瓶100片装。
【诺罗丁Desoxyn 服用方法】
依症状不同，服用的用量也不相同，请咨询主治医师。
Desoxyn
Methamphetamine[note 1] (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.[17] Methamphetamine was discovered in 1893 and exists as two enantiomers: levo-methamphetamine and dextro-methamphetamine.[note 2] Methamphetamine properly refers to a specific chemical, 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. Dextromethamphetamine is a much stronger CNS stimulant than levomethamphetamine.
Both 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, Oceania, and in the United States, where racemic methamphetamine, levomethamphetamine, 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.[note 3] Internationally, the production, distribution, sale, and possession of methamphetamine is restricted or banned in many countries, due 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 sometimes illicitly produced due to the relative ease of synthesis and limited availability of chemical precursors.
In low to moderate doses, methamphetamine can elevate mood, increase alertness, concentration and energy in fatigued individuals, reduce appetite, and promote weight loss. At relatively 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.[21] 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). Heavy recreational use of methamphetamine may lead to a post-acute-withdrawal syndrome, which can persist for months beyond the typical withdrawal period. Unlike amphetamine, methamphetamine is neurotoxic to human midbrain dopaminergic neurons.[22] It has also been shown to damage serotonin neurons in the CNS.[23][24] This damage includes adverse changes in brain structure and function, such as reductions in grey matter volume in several brain regions and adverse changes in markers of metabolic integrity.[24]
Methamphetamine belongs to the substituted phenethylamine and substituted amphetamine chemical classes. It is related to the other dimethylphenethylaminesas a positional isomer of these compounds, which share the common chemical formula: C10H15N1.
Medical uses
Medical
In the United States, dextromethamphetamine hydrochloride, under the trade name Desoxyn, has been approved by the FDA for treating ADHD and obesity in both adults and children;[25][26] however, the FDA also indicates that the limited therapeutic usefulness of methamphetamine should be weighed against the inherent risks associated with its use.[25] Methamphetamine is sometimes prescribed off label for narcolepsy and idiopathic hypersomnia.[27][28] In the United States, methamphetamine's levorotary form is available in some over-the-counter (OTC) nasal decongestant products.[note 3]
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.[25] Methamphetamine hydrochloride dispensed in the United States is required to include a boxed warning regarding its potential for recreational misuse and addiction liability.[25]
Recreational
See also: Party and play and the Recreational routes of methamphetamine administration
Methamphetamine is often used recreationally for its effects as a potent euphoriant and stimulant as well as aphrodisiac qualities.[21]
According to a National Geographic TV documentary on methamphetamine, an entire subculture known as party and play is based around sexual activity and methamphetamine use.[21] Participants in this subculture, which consists almost entirely of homosexual male methamphetamine users, will typically meet up through internet dating sites and have sex.[21] Due to its strong stimulant and aphrodisiac effects and inhibitory effect on ejaculation, with repeated use, these sexual encounters will sometimes occur continuously for several days on end.[21]The crash following the use of methamphetamine in this manner is very often severe, with marked hypersomnia (excessive daytime sleepiness).[21] The party and play subculture is prevalent in major US cities such as San Francisco and New York City.[21][29]
Contraindications
Methamphetamine is contraindicated in individuals with a history of substance use disorder, heart disease, or severe agitation or anxiety, or in individuals currently experiencing arteriosclerosis, glaucoma, hyperthyroidism, or severe hypertension.[25] The FDA states that individuals who have experienced hypersensitivity reactions to other stimulants in the past or are currently taking monoamine oxidase inhibitors should not take methamphetamine.[25] The FDA also advises individuals with bipolar disorder, depression, elevated blood pressure, liver or kidney problems, mania, psychosis, Raynaud's phenomenon, seizures, thyroid problems, tics, or Tourette syndrome to monitor their symptoms while taking methamphetamine.[25] Due to the potential for stunted growth, the FDA advises monitoring the height and weight of growing children and adolescents during treatment.[25]
Side effects
Physical
The physical effects of methamphetamine can include loss of appetite, hyperactivity, dilated pupils, flushed skin, excessive sweating, increased movement, dry mouth and teeth grinding (leading to "meth mouth"), headache, irregular heartbeat (usually as accelerated heartbeat or slowed heartbeat), rapid breathing, high blood pressure, low blood pressure, high body temperature, diarrhea, constipation, blurred vision, dizziness, twitching, numbness, tremors, dry skin, acne, and pale appearance.[25][30]
Meth mouth
A suspected case of meth mouth
Methamphetamine users and addicts may lose their teeth abnormally quickly, regardless of the route of administration, from a condition informally known as meth mouth.[31] The condition is generally most severe in users who inject the drug, rather than swallow, smoke, or inhale it.[31] According to the American Dental Association, meth mouth "is probably caused by a combination of drug-induced psychological and physiological changes resulting in xerostomia (dry mouth), extended periods of poor oral hygiene, frequent consumption of high-calorie, carbonated beverages and bruxism (teeth grinding and clenching)".[31][32]As dry mouth is also a common side effect of other stimulants, which are not known to contribute severe tooth decay, many researchers suggest that methamphetamine associated tooth decay is more due to users' other choices. They suggest the side effect has been exaggerated and stylized to create a stereotype of current users as a deterrence for new ones.[33]
Sexually transmitted infection
Methamphetamine use was found to be related to higher frequencies of unprotected sexual intercourse in both HIV-positive and unknown casual partners, an association more pronounced in HIV-positive participants.[34] These findings suggest that methamphetamine use and engagement in unprotected anal intercourse are co-occurring risk behaviors, behaviors that potentially heighten the risk of HIV transmission among gay and bisexual men.[34] Methamphetamine use allows users of both sexes to engage in prolonged sexual activity, which may cause genital sores and abrasions as well as priapism in men.[25][35]Methamphetamine may also cause sores and abrasions in the mouth via bruxism, increasing the risk of sexually transmitted infection.[25][35]
Besides the sexual transmission of HIV, it may also be transmitted between users who share a common needle.[36] The level of needle sharing among methamphetamine users is similar to that among other drug injection users.[36]
Psychological
The psychological effects of methamphetamine can include euphoria, dysphoria, changes in libido, alertness, apprehension and concentration, decreased sense of fatigue, insomnia or wakefulness, self-confidence, sociability, irritability, restlessness, grandiosity and repetitive and obsessive behaviors.[25][30][37] Peculiar to methamphetamine and related stimulants is "punding", persistent non-goal-directed repetitive activity.[38] Methamphetamine use also has a high association with anxiety, depression, amphetamine psychosis, suicide, and violent behaviors.[39]
Neurotoxicity and neuroimmune response
Unlike amphetamine, methamphetamine is directly neurotoxic to dopamine neurons in both lab animals and humans.[22][23][24] Moreover, methamphetamine neurotoxicity is associated with an increased risk of Parkinson's disease, an effect which partially arises through excessive cytosolic and synaptic production of reactive oxygen species and autoxidation of dopamine.[43][44][45][46][47] In addition to dopaminergic neurotoxicity, a review of evidence in humans also indicated that high-dose methamphetamine use can be neurotoxic to serotonin neurons.[24] It has been demonstrated that a high core temperature is correlated with an increase in the neurotoxic effects of methamphetamine.[48] As a result of methamphetamine-induced neurotoxicity to dopamine neurons, chronic use may also lead to post-acute withdrawal which persists months beyond the typical withdrawal period.[44]
Magnetic resonance imaging studies on human methamphetamine users have also found evidence of neurodegeneration, or adverse neuroplastic changes in brain structure and function.[24] In particular, methamphetamine appears to cause hyperintensity and hypertrophy of white matter, marked shrinkage of hippocampi, and reduced gray matter in the cingulate cortex, limbic cortex, and paralimbic cortex in recreational methamphetamine users.[24] Moreover, evidence suggests that adverse changes in the level of biomarkers of metabolic integrity and synthesis occur in recreational users, such as a reduction in N-acetylaspartateand creatine levels and elevated levels of choline and myoinositol.[24]
Methamphetamine has been shown to activate TAAR1 in human astrocytes and generate cAMP as a result.[49] Activation of astrocyte-localized TAAR1 appears to function as a mechanism by which methamphetamine attenuates membrane-bound EAAT2(SLC1A2) levels and function in these cells.[49]
Methamphetamine binds to and activates both sigma receptor subtypes, σ1 and σ2, in the brain.[42][50] Sigma receptor activation by methamphetamine promotes methamphetamine-induced neurotoxicity by facilitating hyperthermia, increasing dopamine synthesis and release, influencing microglial activation, and modulating apoptotic signaling cascades and the formation of reactive oxygen species.[42][50]
A 2015 review concluded that the behaviour resulting from the use of methamphetamine is likely caused in part from the neurotoxic effects of the drug. Excitotoxicity, oxidative stress, metabolic compromise, UPS dysfunction, protein nitration, endoplasmic reticulum stress, p53 expression and other processes contributed to this neurotoxicity.[51]
Overdose
A methamphetamine overdose may result in a wide range of symptoms.[9][25] A moderate overdose of methamphetamine may induce symptoms such as: abnormal heart rhythm, confusion, difficult and/or painful urination, high or low blood pressure, high body temperature, over-active and/or over-responsive reflexes, muscle aches, severe agitation, rapid breathing, tremor, urinary hesitancy, and an inability to pass urine.[9][30] An extremely large overdose may produce symptoms such as adrenergic storm, methamphetamine psychosis, substantially reduced or no urine output, cardiogenic shock, bleeding in the brain, circulatory collapse, hyperpyrexia (i.e., dangerously high body temperature), pulmonary hypertension, kidney failure, rapid muscle breakdown, serotonin syndrome, and a form of stereotypy ("tweaking").[sources 1] A methamphetamine overdose will likely also result in mild brain damage due to dopaminergic and serotonergic neurotoxicity.[22][24] Death from methamphetamine poisoning is typically preceded by convulsions and coma.[25]
注：药品如有新包装,以新包装为准。以上资讯来源于网络或由高等医药院校的学生志愿者翻译（如有错漏，请帮忙指正），仅供医护人员内部讨论，不作任何用药依据，具体用药指引，请咨询主治医师。
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