How are generic drugs made?

Generic drugs are created by reverse-engineering brand-name drugs after their patents expire. Manufacturers analyze the original drug in labs and recreate them, typically using different excipients (inactive ingredients). The U.S. Food and Drug Administration (FDA) requires these drugs to be bioequivalent to their brand-name counterparts. Bioequivalence means the drug reaches the bloodstream at a similar rate and extent as the original, though a range of variation is permissible—up to 25% more or 20% less absorption compared to the brand name 1.

These drugs are predominantly manufactured in countries like India and China due to lower costs associated with production. While the most generic drugs and drug ingredients are produced overseas, the FDA is mandated to inspect these facilities but often faces logistical challenges, leading to announced inspections. This can result in less stringent checks, potentially affecting the quality observed during these inspections 2.