you shouldn't have a problem. I was also pre-med once upon a time and now I am currently applying to pharmacy school. Most of the pre-pharm and pre-med classes overlapped. You might have to take a couple of extra classes depending on the school you want to attend. The only 2 extra classes I had to take was economics and speech. You should be fine.
I have a friend who was premed too. The pharmD program she went to only made her take some stupid speech class as extra. She went to pharmacy school for 4 year, got a pharmD and is now making $95k/year at Walgreen!
In many cases the pharmd requirements are more rigid than the pre med requirements, as most med schools only require a few basic lit courses, chem, bio, and physics plus 90 semester hours. At least at ULM, the prepharm requirements were very clearly defined, and there were many more required courses. That being said, someone who has finished premed requirements could likely will have all of the prepahrm classes, or at least be close enough that he/she can finish up prepharm work in a semester or so.