Which law created two classes of medications, prescription and nonprescription?

The Durham-Humphrey Amendment of 1951 is significant because it established the legal distinction between prescription and nonprescription medications. This amendment amended the Food, Drug, and Cosmetic Act of 1938 and introduced the concept that certain drugs could only be dispensed with a prescription from a licensed healthcare provider.

Before this amendment, there was no legal framework delineating which medications required a prescription and which could be sold over the counter. The Durham-Humphrey Amendment addressed this by ensuring that medications classified as requiring a prescription were deemed to need supervision from a healthcare professional to ensure safe and effective use by consumers.

The importance of this classification is profound, as it helps to protect patients by ensuring that potentially harmful or complex medications are used appropriately under the guidance of a physician or qualified practitioner.