Amphetamines

Amphetamines are drugs such as dextroamphetamine and benzedrine. Amphetamines were originally developed to treat asthma, sleep disorders (narcolepsy) and hyperactivity. In 1920, a drug called "ephedrine" was used to treat asthma. In China, the ma huang plant (Ephedra vulgaris) had been used for centuries to treat people with asthma. It is no wonder that the plant worked...the ma huang plant contains ephedrine. In 1932, synthetic ephedrine was sold "over-the-counter" and was available without a prescription until 1954. During World War II, amphetamines were given to soldiers and pilots to keep them alert and to fight off fatigue.

Amphetamine Effects on the Nervous System

Amphetamines are stimulants of the central nervous system and sympathetic division of the peripheral nervous system. It appears that the main action of amphetamines is to increase the synaptic activity of the dopamine and norepinephrine neurotransmitter systems. Amphetamines can:

  1. cause the release of dopamine from axon terminals.
  2. block dopamine reuptake.
  3. inhibit the storage of dopamine in vesicles.
  4. inhibit the destruction of dopamine by enzymes.

All of these actions result in more dopamine in the synaptic cleft where it can act on receptors.

Many of the effects of amphetamines are similar to cocaine. Addiction to and withdrawal from amphetamines are both possible. Amphetamine use also causes tolerance to its effects. This means that more and more amphetamine must be used to get "high." Amphetamine withdrawal is characterized by severe depression and fatigue. Users will go to extreme measures to avoid the "downer" that comes when the effect of amphetamines wears off.

Short-term effects of amphetamine use include:

  • Increased heart rate
  • Increased blood pressure
  • Reduced appetite
  • Dilation of the pupils
  • Feelings of happiness and power
  • Reduced fatigue
Long term use of amphetamines can result in:
  • Insomnia, restlessness
  • "Paranoid psychosis"
  • Hallucinations
  • Violent and aggressive behavior
  • Weight loss
  • Tremors



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Take a short on-line, interactive quiz about amphetamines, cocaine and marijuana.

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For more information about amphetamines, see:
  1. Amphetamines - National Clearinghouse for Drug and Alcohol Information
  2. Indiana Prevention Resource Center
  3. Methamphetamine Abuse from the National Institute on Drug Abuse
  4. Methamphetamine May Cause Long-Lasting Brain Damage

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