I'd check the website for the latest info, but when I went in '94 it wasn't anything to stress over. During the day we were in class, and most evenings we were enjoying the San Antonio nightlife.
Class started at about 0730 and went till about 1500 with an hour for lunch around noon. We did PT as a class in the afternoons on MWF. In the begininng things were very basic: customs and courtesies, what it means to be, excpectations of , and how to be an officer, how the Army works stuff, drill and ceremonies, etc. Eventually we got up to basic medical operations planning, NBC, etc. Our first FTX covered simple soldier/CTT skills like land navigation, camouflage yourself and your equipment, weapons training with the M-9.
USUHS does have their MOST (Medical Officer Survival Training) course for those who can't make it to initial officer training.