Question: does omeprazole cause stomach discomfort?
Answer: The most common adverse reactions reported (i.e., with an incidence rate ≥ 2%) from PRILOSEC-treated patients enrolled in these studies included headache (6.9%), abdominal pain (5.2%), nausea (4.0%), diarrhea (3.7%), vomiting (3.2%), and flatulence (2.7%).