Not to mention that all you have to do is look in

Not to mention that all you have to do is look in your medicine cabinet and do a little googling to realize that you can't just patent a mechanism in the body. If you could you'd never have two drugs competing for business. Allegra and Zyrtec never would have come out because Claritin came first. You'd have only one calcium channel blocker, one ace inhibitor, and on and on. Only Viagra, no Levitra or Cialis. (that one was for those of you who only know about the fun stuff)