Final answer:
The Durham Humphrey Amendment defined prescription and OTC drugs by clarifying which medications require a doctor's prescription and which can be sold over the counter. It also permitted oral prescriptions and refills for certain medications.
Step-by-step explanation:
The Durham Humphrey Amendment of 1951 is a significant amendment to the Federal Food, Drug, and Cosmetic Act, which, among other things, defined prescription and over-the-counter (OTC) drugs. This amendment clarified the statuses of medications by determining which ones needed a prescription and which could be sold over the counter. Additionally, this amendment authorized oral prescriptions and refills on certain prescriptions.
Before the amendment, the distinction between prescription and OTC drugs was not clearly defined. The amendment helped to create a safer and more efficient process for drug approval and distribution by ensuring that drugs which could pose a more significant risk to individuals if used without supervision by a healthcare provider were only available by prescription. It is important for drugs to be thoroughly tested and approved to be deemed "safe and effective when used as directed."