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What are active ingredients and inactive ingredients?


An active ingredient (also called an active pharmaceutical ingredient, or API) is the drug itself - the part of a medication that does what the product is designed to do. It is intended to provide what is called "pharmacological activity." Active ingredients affect either the structure or the function of the body when given to prevent or treat a disease or health condition. In short, they are the ingredient or ingredients responsible for the therapeutic action of the medication.

Inactive ingredients, on the other hand, are needed to create the medication's formulation - which could be liquid, pill, capsule, or another form. They are not intended to provide any therapeutic action. Also called excipients, inactive ingredients in drugs are the substances that make up the tablet form or the capsule enclosing the medication, for example, or the liquid in which the API is suspended.

A placebo drug, for instance, contains no active ingredients, only inactive ingredients.

Learn more about your medication.

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Answers to questions regarding information about medications or health conditions are not for diagnostic or treatment purposes and are not conclusive as to the presence or absence of any health condition. Consult your physician for diagnosis and treatment of your medical condition. The information provided is not a substitute for medical advice. Advances in medicine may cause this information to become outdated, invalid or subject to debate. Professional opinions and interpretations of the scientific literature may vary. Walgreens' terms of use and general warranty disclaimer apply to all services provided. If you are in need of immediate medical attention, contact your physician, poison control center or emergency medical professional. If you need to speak with a pharmacist for non-emergency matters, contact your local Walgreens pharmacist or call a pharmacist toll-free at 1 (877) 250-5823.

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