I take Diovan for my blood pressure. I've taken it for 2 and a half years and I believe that my blood pressure is directly related to my weight. You didn't mention how much your mother's weight is.
I have to lose 70-80 pounds and I may try to eliminate my blood pressure medication after I've lost some of that.
I read in the Atkins book about how Beta Blockers and Diuretics can inhibit weight loss, but I'm not sure if my medication is a Beta Blocker or not. I tried to check it out on the internet and couldn't get a clear answer and I haven't had opportunity to check with my doctor.
Anyway, I hope you can get some answers. Hopefully, with the change in diet, blood pressure medication can be eliminated.