Pharmaceuticals and medical devices have life and death implications. But prohibiting a life-saving product is just as deadly as allowing an unsafe one, and there are existing mechanisms that punish the sellers of dangerous products (it comes out and they lose their customers and get sued).
This comes from a facet of human psychology: If you do something and people die then you're a murderer, but if you do nothing and people die you're allowed to shrug and go home. This may be a reasonable heuristic when deciding whether you should do something but it isn't when deciding whether to prevent someone else from doing something.