GERD
"If you have diabetes type 2, I strongly urge you not to take this drug. Even though they say that increase of blood sugar is rare, this happened to me. 
About five days I started taking this drug (40mg), I started to feel lightheaded. 
My morning reading of blood sugar is normally about 6.6 three hours after
breakfast, but I started getting readings of 11.6. I felt like hell. Even worse, the spike in blood sugar caused my blood pressure (controlled by medication) to also spike to about 165/80. I decided to stop the Pantoprazole. The lightheadness went away, and my blood pressure returned to normal. Be very careful with this drug. There are a couple of websites which warn of increase in blood sugar."