The grass is not always greener. What makes you want to jump into another medical profession?
I know several pharmacists who left pharmacy and went to med school. I don't know any physicians who decided to become pharmacists. They might be out there, but it's rare. I knew a dentist who had gone to pharmacy school, but was still working as a pharmacist because she was having a hard time getting into a practice.
I don't know how much credit they'll give you for med school coursework. Many pharmacy schools (just like med schools) are going to an organ system approach. It's difficult to tease out the individual components that you would need. However, I would think you should be able to get out of biochem, physio, and micro at the very least.