In 1951, Congress stopped letting drug makers decide which drugs they would sell over the counter and which would require a prescription and turned that decision over to the FDA. Drugs already available without a prescription were “grandfathered.”
That is why, to this day, people can buy regular and NPH insulin without a prescription. Because those forms of insulin are off‐patent and because consumers comparison‐shop, they are relatively cheap: “ReliOn,” a brand available from Walmart, can cost as little as $25 a vial. Evidence suggests that prescription requirements correlate with higher drug prices and that removing them correlates with reductions in drug prices.