Any suggestions? She used to carry a large Styrofoam cup with a straw wherever she went and periodically add ice ... but she doesn't do that anymore and I need to keep her blood pressure up.
Hot and cold (fruit) soups, fruits, foods with high water or fluid (not sugary) content. Some people will recommend popsicles, which are tasty but also sugary.
Try some Pedialyte or Gatorade. She needs electrolytes, more than just plain water. In a small glass of water you could add a pinch of salt, a pinch of sugar, and a pinch of baking soda instead of plain water.