Amphetamine (alpha-methyl-phenethylamine), also known as speed, is a synthetic stimulant used to suppress 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 most countries).

Due to the widespread use of amphetamines as a treatment for ADD/ADHD in the USA, Canada, and other countries, they frequently find their way onto the street and are one of the most frequently-abused drugs in high schools and colleges.

Patients with acute toxicity from amphetamines may have symptoms of lock-jaw, diarrhea, palpitations, arrhythmia, syncope, hyperpyrexia, and hyperreflexia progressing to convulsions and coma.Patients with chronic use of amphetamines develop a rapid tolerance to the drug and may have to increase the number of pills to reach a desired affect and eventually develop addiction. Patients that develop addiction show symptoms of restlessness, anxiety, depression, insomnia, and suicidal behavior. A urine drug screen can be performed to determine the presence of amphetamines. Patients may need to be hospitalized. Supportive therapy is important. Cooling blankets may be used for hyperthermia. Sedation may be obtained with lorazepam or diazepam. Haloperidol may be given for agitation and delusions. Hypertension and arrhythmias should be treated.

Pharmacology

Amphetamine is a synthetic drug with strong stimulant effects. In the United States, it is most commonly used for treatment of attention-deficit disorders and narcolepsy, but is also approved as a weight-loss

The term amphetamine causes a certain amount of confusion because it is often used incorrectly. In the general sense, amphetamine can describe other drugs with similar, stimulant effects, namely methamphetamine and methylphenidate. Chemists often use the term "amphetamine class" to describe chemicals that are structurally similar (and often similar in effect as well) to amphetamine - namely, chemicals with an ethyl backbone, terminal phenyl and amine groups, and a methyl group adjacent to the amine. A large number of chemicals fall into this category, including the club drug MDMA (Ecstasy) and methamphetamine. It is important to note that such an "amphetamine class" does not technically exist. In the pharmacodynamic sense, these drugs all fall under the umbrella of central nervous system stimulants; in the chemical sense, they are phenylethylamines. Amphetamine, for example, is methylated phenylethylamine, and methamphetamine is double-methylated phenylethylamine.

Amphetamine traditionally comes in the salt-form amphetamine sulfate and is comprised of 50% l-amphetamine and 50% d-amphetamine (where l- and d- refer to levo and dextro, the two optical orientations the amphetamine structure can have). In the United States, pharmaceutical products containing solely amphetamine (for example, Biphetamine) are no longer manufactured. Today, dextroamphetamine (d-amphetamine) sulphate is the predominant form of the drug used; it consists entirely of d-isomer amphetamine, which acts in a slightly different way on the brain than does l-amphetamine. 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.

Amphetamine was first synthesized in 1887 by the Romanian Chemist Lazar Edeleanu, who called it "phenylisopropylamine".

Medicinal use

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), 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, Adderall XR is a timed release formulation

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), 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.

Performance-enhancing use

Amphetamines are usually not used by athletes in sports involving extreme cardiovascular efforts, as methamphetamine and amphetamine put a great deal of additional stress on the heart.

The United States Air Force uses amphetamines (Dexedrine) as stimulants for pilots, calling them "go-pills." After a mission, the Air Force issues a "no-go pill" (Ambien) to help the pilot sleep.

Amphetamines have been popular among some truck drivers, construction workers, and factory workers whose jobs require long or irregular shift work or automatic, repetitive tasks. It is for this reason that they are sometimes labeled a "redneck drug." They are also used by white-collar workers trying to stay alert during long hours of multitasking, and by students hoping to improve their academic performance. There has also been at least one report of the coercive administration of amphetamines to cannery workers in Thailand, in order to enhance productivity (Seabrook, 1996).

Effects of use

Amphetamines release stores of norepinephrine and dopamine from nerve endings by converting the respective molecular transporters into open channels. Amphetamine also releases stores of serotonin from synaptic vesicles. Like methylphenidate (Ritalin), amphetamines also prevent the monoamine transporters for dopamine and norepinephrine from recycling them (called reuptake inhibition), which leads to increased amounts of dopamine and norepinephrine in synaptic clefts.

These combined effects rapidly increases the concentrations of the respective neurotransmitters in the synaptic cleft, which promotes nerve impulse transmission in neurons that have those receptors.

Physiological effects

Short-term physiological effects include decreased appetite, increased stamina and physical energy, increased sexual drive/response, involuntary bodily movements, increased perspiration, hyperactivity, jitteriness, nausea, itchy, blotchy or greasy skin, increased heart rate, irregular heart rate, and headaches. Fatigue can often follow the dose's period of effectiveness. Overdose can be treated with chlorpromazine.

Long-term abuse or overdose effects can include tremor, restlessness, changed sleep patterns, poor skin condition, hyperreflexia, tachypnea, gastrointestinal narrowing, and weakened immune system. Fatigue and depression can follow the excitement stage. Erectile dysfunction, 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.Short-term psychological effects can include alertness, euphoria, increased concentration, rapid talking, increased confidence, increased social responsiveness, nystagmus (eye wiggles), hallucinations, and loss of REM sleep the night after use.

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

Because of the widespread ability in prescription amphetamine today, mainly in the ADD/ADHD medicines Adderall and Dexedrine, there is an increased risk of abuse and addiction among persons of all ages. Tolerance is developed rapidly in amphetamine use, therefore increasing amount of the drug that is needed to satisfy the adiction. Many abusers will repeat the amphetamine cycle by taking more of the drug during the withdrawal. This leads to a very dangerous cycle and may involve the use of other drugs to get over the withdrawal process.

Anyone is able to develope tolerance to amphetamines. Children and other ADD and ADHD sufferers have been known to feel different when not taking the medication, a feeling significantly different enough from being medicated that drives the users to keep taking the drug when it is not needed, however, addiction to ADD/ADHD medication is rare if it is not abused or wrongly prescribed.

Legal issues

• In the United Kingdom, amphetamines are regarded as Class B drugs. The maximum penalty for unauthorised possession is three months' imprisonment and a £2,500 fine.

• In the United States, amphetamine and methamphetamine are Schedule II controlled drugs, classified as a CNS (Central Nervous System) Stimulant. A Schedule II drug is classified as one that: has a high potential for abuse, has a currently-accepted medical use and is used under severe restrictions, and has a high possibility of severe psychological and physiological dependence.

On the international scene, amphetamine is a Schedule II drug under the Convention on Psychotropic Substances.

Books

See also

• Adderall
• Stimulants
• Phenethylamines
• Dextroamphetamine (Dexedrine)
• Methylphenidate (Ritalin, Concerta)
• Cathinone
• Methcathinone
• Ephedrine
• Tolerance
• Attention Deficit Hyperactivity Disorder
• Psychoactive drug
• Clandestine chemistry
• Uncle Fester (author)

Notes

1.   Amfetamin

Amphetamin Anfetamina Amphétamine Anfetamina אמפטמין Amfetamin Amfetamina Amfetamine アンフェタミン Amfetamin Amfetamina Anfetamina Амфетамин Amfetamiini Amfetamin Амфетамін 苯丙胺