Plain English Meaning

A prescription painkiller in the same family as morphine. It dulls pain but also dulls the mind and reflexes, so a pilot cannot safely fly while it is in their system.

Full Definition

A synthetic opioid pain reliever (analgesic) used medically to treat moderate to severe pain. As a central nervous system depressant, it causes drowsiness, impaired judgment, slowed reaction time, and reduced coordination, and is therefore disqualifying for flight while it remains active in the body.

Context Anchor

Seen in FAA drug and medical fitness discussions, especially when reviewing medications that can impair a pilot.

Derivation

Meperidine is a brand-neutral name coined in the 1930s for the synthetic compound also known as pethidine. The name has no everyday English meaning, which matters: a pilot reading a prescription label may not recognize it as an opioid unless they know the term.