Some gastrointestinal symptoms can be relatively minor and short-lived and are easily treated with over-the-counter medicines. For example, indigestion and acid reflux can be treated with antacids or medicines such as omeprazole and ranitidine. Symptoms of irritable bowel syndrome (IBS) can be relieved with mebeverine or hyoscine. Ask a pharmacist for advice on which medicines are most suitable for you. If any gastrointestinal symptoms are worrying or last longer than about two weeks, make an appointment to see your doctor. More severe conditions – for example, ulcerative colitis and Crohn's disease – are treated with medicines such as budesonide, prednisolone and mesalazine.