What Is Amphetamine?

Jessica Clifton

by Jessica Clifton

6th May 2020

What is amphetamine? Well, amphetamines are a class of drugs that stimulate the central nervous system. They are also known as psycho-stimulants, and are sometimes used as a treatment for those who have the following disorders:

  • Attention deficit hyperactivity disorder (ADHD)
  • Narcolepsy
  • Parkinson’s disease
  • Obesity

Although amphetamine has medical uses, it is also an addictive drug that has the tendency to be abused. Hence, it is classified by UK law as Class B or controlled drugs that have corresponding penalties.

Amphetamine is designated as controlled under the Misuse of Drugs Act 1971. The possession, sale, and manufacture of amphetamine without proper authorisation have corresponding penalties of imprisonment and fines.

The recreational use and abuse of amphetamine are prohibited, yet it remains one of the most popular illicit drugs in England. It is commonly known as speed, and other colloquial names include amph, whiz, billy, sulph, and uppers.

What do amphetamines do?

Ephedra (scientific name Ephedra sinica) is the plant source of amphetamines. This plant is native to China and Mongolia and has been known for its medicinal properties since ancient times. It is mainly used as a recreational stimulant but is also used in folk medicine as a treatment for congestion and asthma.

Ephedrine and pseudoephedrine are the active alkaloid contents of the plant that have physiological effects on humans. These alkaloids are extracted and purified and serve as the molecular basis for the synthesis of amphetamines, which includes the more potent drug, methamphetamine.

As stimulants, amphetamines increase chemical activity in the brain that allow a person to be wide awake and physically active. When a person takes amphetamines, their alertness and sense of wellbeing are heightened and they tend to become hyperactive.

However, when the effects of the drug subside, they may feel lethargic. Over time, dependency or addiction may develop. An addict may become paranoid and emotionally unstable because of the lack of sleep.

Amphetamines have both short-term and long-term effects. Some are minor impacts on health but others can be life-threatening.

How do amphetamines work?

As stimulants, amphetamines trigger the ‘fight or flight’ response of the brain. The drug molecules bind with specific receptors that prompt the release of certain hormones responsible for alertness and survival mode.

Amphetamines prompt the ‘flight or fight’ response through the following processes: 

  • Adrenalin, insulin, and other stress hormones are released into the bloodstream
  • Heart rates and blood pressure increase
  • Blood supply and blood flow to the peripheral muscles increases
  • The muscles become tense and your metabolism goes into hyper-drive

Several ‘designer’ drugs are derived from amphetamines. They have similar molecular structures that bind with specific receptors in the brain. These some examples of drugs that are based on amphetamines. They are branded prescription drugs for the treatment of certain disorders like ADHD.

  • Methamphetamine
  • Adderall
  • Adderall XR
  • Dexedrine
  • Methylphenidate (Ritalin)
  • Concerta
  • Procentra

Some illicit designer drug versions of amphetamine are also available on the black market. These are usually combinations or derivatives of amphetamine and methamphetamine. Aside from being stimulants, these drugs are also hallucinogens. They have psychedelic effects.

  • Methcathinone (“Cat”)
  • Methylenedioxy-n-methylamphetamine (MDMA, ecstasy)
  • Methylenedioxyamphetamine (MDA)

Amphetamines give short-term highs and a feeling of wellbeing or alertness. When taken in small doses, they are effective in banishing the feeling of tiredness, but that’s only short-lived. Addicts who try to stop their addiction experience withdrawal symptoms that include:

  • Feeling nauseous
  • Irritability
  • Depression 
  • Extreme exhaustion

What’s the chemical name for amphetamine?

Just like other complex organic chemicals, the chemical name for amphetamine is based on the International Union of Pure and Applied Chemistry (IUPAC) standards of nomenclature. Its IUPAC chemical name is 1-phenylpropan-2-amine. The name indicates the functional groups and the position of the molecules.

The IUPAC name is so precise that if you are familiar with the nomenclature conventions, you can visualise the molecular structure of the chemical. It is also known by other chemical names such as amphetamine, which is the International Non-Proprietary Name or INN. Other names commonly used for amphetamine include 1-phenyl-2-aminopropane and phenyliospropylamine.

Amphetamine chemical structure

The chemical formula for amphetamine is C9H13N. This simply tells us that in a molecule of this substance, there are nine carbon atoms, thirteen hydrogen atoms, and one nitrogen atom. This type of representation is not insightful when it comes to analysing how the molecule works.

The chemical formula of amphetamine

Amphetamine binds with receptors in the brain to prompt the production of certain hormones and neurotransmitters. Hence, the chemical structure or molecular structure plays an important role here.

A molecule of amphetamine has an amine group (with nitrogen), a methyl group, and a benzene ring group. The molecule has rewarding and reinforcing effects by triggering an elevated level of extracellular dopamine. It prolongs the signalling of the dopamine receptor.

Amphetamine has three major mechanisms in the brain:

  1. It acts as a substrate for the dopamine transporter, which inhibits dopamine uptake
  2. It facilitates the movement of dopamine out of vesicles into cytoplasm
  3. Finally, amphetamine promotes dopamine transporter-mediated reverse-transport of dopamine into the synaptic cleft

What are the side effects of amphetamine?

If taken in higher doses, some of the common short-term side effects of amphetamine include:

  • Pale skin
  • Delusion of being powerful
  • Obsessive and repetitive movement
  • Irregular breathing
  • Bradycardia and tachycardia
  • Clamping jaw and grinding teeth
  • Panic attacks
Side effects of taking amphetamine include aggression, emotional instability, and psychotic episodes

Side effects of taking amphetamine over time include aggression, emotional instability, and psychotic episodes

Once a person becomes addicted and uses the drug more frequently, some of the long-term effects of taking amphetamine include: 

  • Loss of appetite that sometimes results in malnutrition and extreme weight loss
  • Weakening of the immune system, which makes a person more vulnerable to infections
  • Tendency to become impulsive and violent in behaviour
  • Emotional instability or mood swings
  • Periods of psychotic behaviour

How long do amphetamines stay in your system?

The duration of detectable amphetamine in your system varies. It depends on several factors, including:

  • Amount of drug taken
  • Type of amphetamine
  • Body type
  • Metabolic rate
  • Water and food intake

The detectability of this drug also depends on the type of sample of body fluid or specimen that’s tested. It also depends on the quality of the test method.

  • Generally, detectable traces of amphetamines stay in the human body between two (2) to five (5) days
  • It can be detected in urine for up to four (4) days
  • It is detectable in your hair for up to ninety (90) days

Is cocaine an amphetamine?

Knowing what amphetamine is also means knowing what it is not. Some may wonder if cocaine is a type of amphetamine. Chemically speaking, cocaine has the formula C17H21NO4 while amphetamine has the formula C9H13N.

Obviously, they are not the same compounds but they have similar compositions and molecular structures. Both are classified as stimulants and both have similar effects in terms of prompting dopamine production.


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