I concur with trolleater, call your husbands doctor for clarification and inform the doctor of your husbands discomfort with
Glipizide. He/she should never changed
medications w/o first informing your husband and explaining the reason why.
I'm unsure on the dosage equivalency of Glipizide vs Glyburide. Both are in the same class of diabetes medications but Glipizide is short/rapid acting while Glyburide is slow/long acting.