What are unapproved drugs and why are they on the market?

What are unapproved drugs and why are they on the market?
Federal law generally requires that drugs in the United States be shown to be both safe and effective prior to marketing. Drugs that are marketed without required FDA approval may not meet modern standards for safety, effectiveness, quality, and labeling. For a variety of historical reasons, some drugs, mostly older products, continue to be marketed illegally in the United States without required FDA approval. Many healthcare providers are unaware of the unapproved status of these drugs and have continued to unknowingly prescribe them because the drugs’ labels do not disclose that they lack FDA approval.

In 1962, Congress amended the 1938 Food, Drug and Cosmetic Act to require manufacturers to show that their drug products were effective, as well as meeting the requirement of the earlier Act, that the products must be safe. As a result, all drugs approved under New Drug Applications (NDAs) between 1938 and 1962 had to be reviewed again for effectiveness. To be consistent with current regulations and to ensure that all drugs have been shown to be safe and effective, all drugs are required to have an approved application for continued marketing.

Since many unapproved products are marketed without brand names and have been available for many years, it is often assumed that these unapproved products are generic drugs. This is not correct. Generic drugs have been tested and shown to be the same (bioequivalent) as brand name drugs. Unapproved drugs have not been tested for safety and effectiveness nor tested and shown to be the same as an approved drug. Therefore, they are not generic products.

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What are unapproved drugs and why are they on the market?