Excipient

Definition

An inactive ingredient in a drug formulation that serves a purpose other than the therapeutic effect — such as binding, filling, flavoring, coloring, or preserving the medication. While pharmacologically inactive, some excipients can cause allergic reactions in sensitive individuals.

Example

Lactose is a common excipient used as a filler in tablets; patients with severe lactose intolerance may need lactose-free formulations.

Related Terms

Active Ingredient API Enteric Coating Inactive Ingredient

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