Active ingredient


Written By: Ehsan Jahandarpour

An active ingredient is the ingredient in a pharmaceutical drug or pesticide that is biologically active. The similar terms active pharmaceutical ingredient (also abbreviated as API) and bulk active are also used in medicine, and the term active substance may be used for natural products. Some medication products may contain more than one active ingredient. The traditional word for the active pharmaceutical agent is pharmacon or pharmakon (from Greek: φάρμακον, adapted from pharmacos) which originally denoted a magical substance or drug.