Hello, Thanks for posting in HCM. Prilosec (omeprazole) and protonix (pantoprazole) are drugs of same group ie Proton pump inhibitors. Both these are almost equal in effectiveness but subjective cases show omeprazole to be more effective. So if you felt better with Prilosec, you can go back to it with the same frequency of dosage as you were advised by your doctor. Taking these meds is the treatment for acid reflux disease. Also you have to take the tablet half hour before breakfast empty stomach. If you take any late than this or just before you start eating then it won’t be as effective as that may be the reason for you not feeling it effective. I hope I answered your question satisfactorily. If you have any more query kindly write back to me, will be happy to help you out. Thank you.