This question (or similar) have been asked here with some frequency. The short answer that is typically given is; finish your current degree and go for a non-arch background masters degree with is 3 years instead of 5. 

As someone who is restarting school for the second time, take that advice (assuming you are in the US.) I'm 25 and have peers that are on to their doctorate degrees while I'm wandering around with my HS diploma an 90 disjointed college credits.  

Second this - finish, then get your Masters in Architecture. That business degree is going to help you out.

Agree with the rest - finish your undergrad in business then go for your Master of Architecture. It's not an uncommon route. Even if you switched to a BS Arch, you would likely still need a Master's degree anyways to work in the field (unless you meant B.Arch)

If you have time in your curriculum or outside of school though and you truly are interested in architecture, you should think about taking a course (whether it be anything from arch history/visual arts/3D design) or work on a side project that will help with your M.Arch application portfolio

I did not read the 'f' in the title until my second take... that along with the different meaning for BS and I gave myself a chuckle.  Thought I'd share