API refers to the key ingredient or chemical that makes the drug work. While a finished formulation or a formulation intermediate is the process in which different chemicals including the active ingredients are mixed in specific ratios to produce a specific drug. API (Active Pharmaceutical Ingredient): The ...

An active ingredient is any ingredient that provides a biologically active or other direct effect in the diagnosis, cure, mitigation, treatment or prevention of disease or to affect the structure or function of the human or animal body. Similar terms active pharmaceutical ingredient (also abbreviated ...