Adverse Effect
1 Definition of Adverse Effect
Meaning of Adverse Effect: An unwanted or harmful outcome associated with a medication or intervention.
An adverse effect is an unintended, harmful, or unpleasant response linked to a drug, treatment, or procedure. It may occur at normal use or dose and ranges from mild to severe.
Also known as
adverse reactionside effect
Used in a sentence
Nausea was documented as a possible adverse effect of the medication.
Good to know
An adverse effect is not always an allergy; allergies involve a specific immune response.
Word origin
Where “Adverse Effect” comes from
Adverse comes from Latin adversus, meaning “turned against.”