Plain English Meaning

A group of strong stimulant drugs that speed up the brain and body, making a person feel more awake and energetic. They are unsafe for flying because they distort judgment and cause a sharp crash when their effects fade.

Full Definition

A class of stimulant drugs that act on the central nervous system to increase alertness, suppress fatigue, and elevate mood. Amphetamines are commonly prescribed for conditions such as attention deficit disorder and narcolepsy, and are also widely abused. Use of amphetamines disqualifies a pilot from flying under FAA regulations unless specifically approved, because they can cause overconfidence, impaired judgment, irritability, and a dangerous letdown effect when the drug wears .