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Amphetamine (alpha-methyl-phenethylamine), also known as speed or crank, is a stimulant used to diminish the appetite, control weight, and treat disorders including narcolepsy and attention-deficit hyperactivity disorder. It is also used recreationally and for performance enhancement (these uses are illegal in some countries). Illicit production and use of amphetamines occurs on a widescale basis in several European nations, typically in the form of amphetamine sulfate synthesized from phenylpropanolamine. In addition, because of the widespread use of amphetamines as a treatment for narcolepsy and ADD/ADHD, prescription amphetamines are subject to diversion and are one of the most frequently-abused drugs in high schools and colleges. Toxicity Chemistry Traditionally the medical drug came in the racemic salt-form rac-amphetamine sulfate (rac = levo- and dextro-form in equal amounts). In the United States, pharmaceutical products containing solely rac-amphetamine are no longer manufactured. Today, dextroamphetamine sulphate is the predominant form of the drug used; it consists entirely of the d-isomer. Attention disorders are often treated using Adderall or generic-equivalent formulations of mixed amphetamine salts that contain both d/l-amphetamine and d-amphetamine in the sulfate and saccharate forms mixed to a final ratio of 3 parts d-amphetamine to 1 part l-amphetamine. Pharmacology Dextroamphetamine, the eutomer of amphetamine, exhibits its mode of peripheral action via release and reuptake inhibition of the monoamine neurotransmitters acetylcholine (ACh) and histamine (H), but not glutamate. Its activity at the vesicular monoamine transporter VMAT2 is of crucial importance in the release process. Application range Medicinal use * Diet suppressant Recreational uses: * Stimulant Other uses: * Used by the US military to combat fatigue and increase wakefulness Contraindications: * CNS Stimulants Side effects: * Dizziness Cardiovascular: * Bronchodilator Ear, nose, and throat: * Decongestant Eye: * Mydriasis (Pupil dilation) Gastrointestinal: * Diarrhoea Musculoskeletal: * Muscle aches/cramps Neurological: * Dopamine Agonist Respiratory: * Bronchodilator The experimental medical use of amphetamines began in the 1920s. It was introduced in most of the world in the form of the pharmaceutical Benzedrine in the late-1920s. The drug was used by the militaries of several nations, especially the air forces, to fight fatigue and increase alertness among servicemen. After decades of reports of abuse, the FDA banned Benzedrine inhalers, and limited amphetamines to prescription use in 1959, but illegal use became common. Along with methylphenidate (Ritalin, Concerta, etc.), amphetamine is one of the standard treatments for ADHD. Beneficial effects for ADHD can include improved impulse control, improved concentration, decreased sensory overstimulation, and decreased irritability. These effects can be dramatic, particularly in young children. The ADHD medication Adderall is composed of four different amphetamine salts, and Adderall XR is a timed release formulation of these same salt forms. When used within the recommended doses, side-effects like loss of appetite tend to decrease over time. However, amphetamines last longer in the body than methylphenidate (Ritalin, Concerta, etc.), and tend to have stronger side-effects on appetite and sleep. Amphetamines are also a standard treatment for narcolepsy as well as other sleeping disorders. They are generally effective over long periods of time without producing addiction or physical dependence. Amphetamines are sometimes used to augment anti-depressant therapy in treatment-resistant depression. Medical use for weight loss is still approved in some countries, but is regarded as obsolete and dangerous in, for example, the United States.
These combined effects rapidly increase the concentrations of the respective neurotransmitters in the synaptic cleft, which promotes nerve impulse transmission in neurons that have those receptors. Physiological effects * Long-term abuse or overdose effects can include tremor, restlessness, changed sleep patterns, anxiety and increase in pre-existing anxiety, poor skin condition, hyperreflexia, tachypnea, gastrointestinal narrowing, and weakened immune system. Fatigue and depression can follow the excitement stage. Erectile dysfunction (Wizz dick), heart problems, stroke, and liver, kidney and lung damage can result from prolonged use. When snorted, amphetamine can lead to a deterioration of the lining of the nostrils. Psychological effects * Long-term psychological effects can include insomnia, mental states resembling schizophrenia, aggressiveness (not associated with schizophrenia), addiction or dependence with accompanying withdrawal symptoms, irritability, confusion, and panic. Chronic and/or extensively-continuous use can lead to amphetamine psychosis, which causes delusions and paranoia, but this is uncommon when taken as prescribed. Amphetamine is highly-psychologically addictive, and, with chronic use, tolerance develops very quickly. Withdrawal is, although not physiologically threatening, an unpleasant experience (including paranoia, depression, difficult breathing, dysphoria, gastric fluctuations and/or pain, and lethargia). This commonly leads chronic users to re-dose amphetamine frequently, explaining tolerance and increasing the possibility of addiction. Addiction Legal issues Internationally, amphetamine is a Schedule II drug under the Convention on Psychotropic Substances.
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