Oesophageal ulcer. Gross clinical specimen of an ulcerated human oesophagus (gullet). This condition may be due to acid reflux, which occurs when the muscles of the lower oesophagus are weakened, allowing reflux (regurgitation) of the acidic stomach juices up the oesophagus. Antacid drugs, which reduce the acidity of the stomach fluids, can provide short term relief. Ultimately, a change in life style and eating habits is needed, although in the case of severe ulceration surgical treatment may be required.