Biology - You'll need the general biology courses, which are a walk in the park. Then there's the anatomy and physiology and microbiology courses which involve considerable more studying then the general courses.
Calculus - Enjoy a full year of calc, it'll piss you off when you finish once you realize how easy the class really is.
Chemistry -Learn to love Chemistry because you will be its bitch for the next 6-8 years of your studying. Pharmacy is Chemistry. General Chem is a fairly simple class once you wrap your mind around it. Organic Chemistry will whoop your ass back to the 17th century. I am not exaggerating that at all. To put it in layman's terms imagine having to know exactly what will happen when you combine to materials down to a molecular level. It will make you cry at night.
Then there is Biochemistry. You will take this again upon entering pharmacy school, but its still not a bad idea to take it in your undergrad. If O Chem knocks you back to the 17th century, this course will kick your ass back into a fetus. The course itself is not overly difficult, but the sheer amount of material you learn is astounding. You literally learn how your your body takes the food you eat and converts it to energy. You will learn that pathway like the back of your hand.
Then there is a year of physics, your English, History, and other gen eds. One top of that you essentially need to average an B+/A- in all those courses to even be considered.
And that is why I drink so much at times. Only way to relieve the stress.
That being said if anyone does have any questions, especially those of you in college, I will be willing to answer them. I am going to be an Organic, and probably Biochem, tutor next fall so I can help answer questions and such. To you others, I hope this was a slightly more enlightening experience.