Question: can omeprazole cause tummy ache?
Answer: Common side effects include headaches, diarrhoea and stomach pain. These tend to be mild and go away when you stop taking the medicine. If you're self-treating with omeprazole, do not take it for longer than 2 weeks without checking with a doctor. Omeprazole is also called by the brand names Losec and Losec MUPS.