Well at my school, pharm is a 1 week course where you learn the basics (loading dose, maint. dose, competitive/noncomp inhibition, etc etc.) of pharmacodynamics and pharmacokinetics. Then we learn about each individual drug later during the respective organ systems courses.
In my opinion, taking an undergrad course in pharmacodynamics/kinetics may be a waste of time, since the basic pharm course they teach in med school is fairly easy and straightforward and only takes 1 week. Even if your undergrad pharm course teaches about specific drugs and their mechanism of action and side effects, I don't see how it'd be useful since you wouldn't have had much exposure to pathology yet, and besides, new drugs come out all the time and treatment standards change so frequently that whatever you might learn in your undergrad course might not apply by the time you learn it again in med school.
Anyway, just my 2 cents.