Depends where it's from and what you want to do. In terms of job opportunities after graduation, doesn't make a substantial difference, as you won't be hoisted to a managerial position straight after you graduate. Reception is mixed too - some will see it as a positive while others will wonder why you bothered to get one without any real world experience to integrate what you've learned. It also closes doors - you will have an almost-zero shot of studying for a second MBA at a better school because they will look at your motives with suspicion. One of the benefits of getting an MBA is the network to which you gain access. For the great majority of pharmacy schools that offer MBAs, their networks pale in comparison to the top 50 business schools'.
All in all, understand why you feel you need to get the dual degree so that you can articulate your reasoning to people who will ask - and I'm certain that you will be asked. Can it open doors? Sure, but again, that will depend on what you're looking to do. The dual degree may save you a year of time and tuition. If you want to be a DM at a retail chain or DOP at a hospital, it may not matter which school you get your MBA at, so long as you have one. If your goal is simply to get hired as a retail pharmacist, then you don't need one; your time would be better served elsewhere. You should ask yourself, "Why now? Why not later? Why not an online or an EMBA program when I actually see a need for it?"