An active pharmaceutical ingredient (API) is the part of any medication that produces the intended health effects. Learn why it's important to know what that is before taking one. An active ingredient is any ingredient that provides biologically active or other direct effect in the diagnosis, cure, mitigation, treatment, or prevention of disease or to affect the structure or any function of the body of humans or animals. An active ingredient is any component that provides pharmacological activity or other direct effect in the diagnosis, cure, mitigation, treatment, or prevention of disease, or to affect the. Active ingredients are the chemical compounds in medicines that have an effect on the body. Essentially, they are the ingredients within your medicine that make the medicine work. Active Ingredient Any component that provides pharmacological activity or other direct effect in the diagnosis, cure, mitigation, treatment, or prevention of disease, or affects the structure or any function of the body of man or animals. Most medications are made of a combination of active and inactive ingredients. Active pharmaceutical ingredients (also called APIs) provide the therapeutic effects of the medication. What are active ingredients? The active ingredients in medication are the components that trigger the effect you are looking for. For example, the active ingredient in blood pressure medication is the compound that works to lower your blood pressure. An active ingredient is any ingredient that provides biologically active or other direct effect in the diagnosis, cure, mitigation, treatment, or prevention of disease or to affect the structure or any function of the body of humans or animals. Search or browse our A-Z lists of active ingredients available in the United States. Access drug & treatment information, identify pills, check interactions and set up personal medication records. Subscribe to our newsletter for the latest medication news, new drug approvals and FDA alerts. Most medicines contain two categories of ingredients: the active ingredient that treats your condition, and a collection of inactive ingredients that hold the pill together, protect it, and help your body absorb it.