Hi traciboop,
I will let you know that diamox is a diuretic that helps get rid of extra fluids in the body. Just like you I've taken both tegretol and tegretol xr but never at the same time. In case your Dr. hasn't told you never eat grapefruit or drink grapefruit juice while on tegretol or tegretol xr because the enzymes in the fruit can mess up the drug and cause many problems.
As far as the diamox goes you may notice that you don't want to eat that much and that's because the drug makes you feel full but other than that I've had no other side effects from the drug. I wish you the best of luck and May God Bless You!

Sue