Actually in medicine we have both the good and bad of patents. For any drug to be brought to market in the U.S. there is, by necessity, a long and expensive process to ensure a drug does more benefit than harm. This process can cost millions of dollars but producing the formula + manufacturing is often not nearly as expensive. Hence, a patent, because of the legal framework for which these inventions are conceived within, granting a monopoly for a short period of time is the only thing that promotes or gives companys an incentive to continue on with FDA approval.

This, by the way, is no means or excuse for some of the shenanigans drug manufacturers take part in. It merely is one illustration of why a patent system should exist.