An active ingredient is the part of a medicine that produces its intended effect. In other words, it is the ingredient responsible for what the medicine is designed to do.
Why the Active Ingredient Matters
Different medicines can have different brand names but contain the same active ingredient. Checking the active ingredient can help you avoid accidentally taking two products that contain the same medicine.
Where to Find It
On over-the-counter medicines in the United States, the active ingredient appears near the top of the Drug Facts label.
The label also tells you how much of the active ingredient is contained in each dosage unit, such as each tablet, capsule, or measured amount of liquid.
Active Ingredient vs. Purpose
The active ingredient tells you which substance in the product produces the medication effect.
The Purpose section tells you what type of medicine it is, such as a pain reliever, antihistamine, antacid, or cough suppressant.
Can a Medicine Have More Than One Active Ingredient?
Yes. Some combination products contain two or more active ingredients.
For this reason, it is important to read the Drug Facts label carefully, especially when using more than one over-the-counter product at the same time.
What About Inactive Ingredients?
Inactive ingredients are the other components used to make the product. These may include ingredients such as colors, flavorings, or binders.
They are different from the active ingredient because they are not intended to provide the main therapeutic effect of the medicine.
A Simple Example
For example, a pain-relief product may list acetaminophen as its active ingredient. The Purpose section may identify it as a pain reliever and fever reducer.
Always check the full Drug Facts label before using an over-the-counter medicine.
When to Ask a Pharmacist or Doctor
If you are unsure which active ingredient a product contains, are taking multiple medicines, or have questions about whether products can be used together, ask a pharmacist, physician, or other qualified healthcare professional.
Sources
- U.S. Food and Drug Administration (FDA). The Over-the-Counter Drug Facts Label.
- U.S. Food and Drug Administration (FDA). Drugs@FDA Glossary of Terms.