I greatly enjoy working both. My advice, whichever job you take, see if you can do PRN work at the other job, so you will always have a leg in the door. Unfortunately, in today's climate, its difficult to jump from retail to hospital or hospital to retail, if one only has experience in one (although certainly not impossible!)
Speaking in generalities, since every individual job is different (and the tone is often set by the manager/director)...
hospital: considerably less pay, but considerably more vacation time. More working of holidays & having to cover other shifts if someone is sick. More likely to have a set schedule (ie all first shift, all second shift, etc.) Most of the time, there is no personal knowledge of the difference you've made in someone's life (recovered people will send candy & flowers to the nurses to thank them, pharmacy never.) More likely to see unique things and use a broader range of your pharmacy knowledge. Co-workers more likely to be gossipy, department wars, and the politics if one gets into management can be unbearable. Often a lot of on-call, and even unofficial on-call. MUCH more sitting (good if you are already in bad shape and have problems standing, problematic if you are already in good shape as it can lead to health problems from being too inactive.) Food....could be good or bad, depending on the individual hospitals cafeteria. More impressive to potential dating partners to say you work for ABC Hospital than to say you work for ABC chain/independent pharmacy. Electricity goes out, generators kick on, and you have to keep working.
retail: considerably more pay, but less vacation time. Much easier to get a particular day off & to have holidays off, but schedule much more variable. Generally a bigger PRN pool, so you are less likely to have to cover sick calls at the last minute. Gratifying to see first-hand the difference you can make in someone's life, especially in knowing that a specific solution proposed by you, really helped with their problem when they come back to thank you in person. MUCH easier to get decent parking. Have to deal with the public, an experience which people who have never done so won't understand. Pretty much NO on-call, when you leave work, you are done and your time is your own. MUCH less gossip & politics between co-workers (probably due to the public always hovering around and if you work for a chain, the higher-ups working a distance away.) MUCH more on your feet (good for you health if you are in good shape, problematic and possibly impossible if you are not in good shape.) Food....could be good or bad depending on the restaurants that are in that delivery area. Electricity goes out, probably no generators, and you won't have to do any work (just hope its time for the next shift before it comes back on!)