What Is an Active Pharmaceutical Ingredient (API)?

The active pharmaceutical ingredient (API) is the part of any medication that produces the intended health effects. The APIs are produced from raw materials, with a specified strength and chemical concentration. Some drugs, such as combination therapies, have multiple APIs that may act in different ways or treat different symptoms.

drug manufacturing
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Components of Medications

Drugs are manufactured under stringent conditions to maintain consistency and minimize the risk of contamination.

All drugs are made up of two core components:

  • The API is the central ingredient.
  • The excipient includes substances other than the drug that help deliver the medication to your system.

Excipients are chemically inactive substances, such as lactose or mineral oil in the pill. These materials are used to help the medication remain stable and to control absorption when you take the drug. Excipients should not have any effect on your health unless you are allergic to them.

Strength of APIs

Manufacturers use certain standards to determine how strong the API is in each drug. The FDA requires equivalency testing for generic drugs to ensure that they are of the same potency as the brand versions.

Manufacturers are required by the FDA to prove the potency of their products in laboratory conditions and in real-life patients.

Top API Manufacturers

A leading manufacturer of APIs is TEVA Pharmaceuticals. Another leading manufacturer is Dr. Reddy's.

Other industry giants are Pfizer, Novartis, Sanofi, Boehringer Ingelheim, and Bristol-Meyers Squibb. Each of these companies specializes in different APIs, with some offering generic products as well.

Where Are APIs Made?

Production of APIs has traditionally been done by pharmaceutical companies in their home countries. In recent years many corporations have opted to send manufacturing overseas to cut costs on expensive equipment, employees, infrastructure, procurement alliance, and supplier compliance. While this has helped their bottom line, there is continued concern about the quality of APIs produced overseas.

This has caused significant changes to how these drugs are regulated, with rigorous Federal Drug Administration (FDA) guidelines and inspections put into place.

While many pharmaceutical companies are located in the United States and England, most API manufacturers are overseas.

Other than the U.S., the largest are located in Asia, particularly in India and China, according to the FDA.

A Word From Verywell

When you are taking any prescription or over-the-counter drug, it's important that you get your medication from a reputable retailer or pharmacy. If you have any questions or concerns, talk to your pharmacist, who will be able to answer your questions.

3 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Food and Drug Administration. Generic drugs: Questions and answers.

  2. Food and Drug Administration. Guidance for industry, good manufacturing practice guidance for active pharmaceutical ingredients.

  3. Food and Drug Administration. Safeguarding pharmaceutical supply chains in a global economy.