Here is a link that I found on Lepto shots, I do not give Lepto to any of my Adult Yorkies or puppies. I would call your Vet and get more info on this, and your should never give two shots in one like the Rabies and the Leptos always do this on 3 to 5 days apart of each other.
http://www.yorkietalk.com/forums/sho...ght=Lepto+shot