Taking 40 milligrams of Omeprazole every day can be harmful, states Drugs.com. Using it for more than a year may increase the risk for spine, wrist or hip fractures. Forty milligrams orally, once daily for four to eight weeks, is the recommended dose for adults with duodenal or gastric ulcers.
Hypomagnesemia, including arrhythmias and seizures, has been reported in patients who take Omeprazole for three months to a year or more, notes Drugs.com. Evidence of atrophic gastritis has been observed in biopsies taken of deceased patients who were treated with Omeprazole on a long-term basis. Studies show a relationship between therapy using drugs such as Omeprazole and development of diarrhea associated with Clostridium difficile. Patients taking Omeprazole should use the lowest dose and the shortest period of time recommended to treat their conditions.