Inactive Ingredient
Definition
Any component of a drug product other than the active ingredient. Inactive ingredients include binders (hold tablets together), fillers (bulk up the tablet), disintegrants (help tablets break apart), flavoring agents, and preservatives. While they don't produce therapeutic effects, they can occasionally cause allergic reactions.
Example
FD&C Yellow No. 5 (tartrazine) is an inactive ingredient (coloring agent) that can cause allergic reactions in some people, particularly those with aspirin sensitivity.