There is a difference.

Normally I suffer a typical symptoms. Upper throat. Normal heartburn hasn't been an issue for 6 months. However, I had to switch pharmacies and get my meds mailed to me and there was a delay. They sent them to the wrong address. So I have had to take the generic form of protonix. With in a few days I am now suffering very normal heartburn symptoms. Lower throat and trouble swallowing.
My brand name gets here today hopefully. To me, there is a BIG difference between brand name and generic.
about 6 months ago I was having very little luck and switched and my troubles nearly went away. Brand vs generic for Protonix. Try it yourself. I have to pay 25 dollars for brand name.

I also had the same experience with protonix.  I was put on IV protonix while I was in the hospital with my bleeding ulcers.  They gave me a prescription for it when I got out.  But after the first month , I had to renew my prescription and opted for the generic because at the time, the brand name cost $200 for a month which was terribly expensive.  I was very happy with the brand name but the generic version caused me all kinds of problems.  Heartburn, stomach aches.  So I started trying different PPI's.  I finally settled on Prevacid but it also has to be the brand name, not the generic.  I guess some of us are just more discriminating.  LOL!