Bad oral hygiene can lead to sour taste. Excess use of tea, caffeine, cocaine and tobacco can cause sour mouth. Injuries to nerves or brain can lead to sour taste. If you are suffering with depression, stress disorders or anxiety, it may also be a cause of sour taste in the mouth.
Health conditions. Certain health conditions can cause symptoms of flatulence, including: 1  indigestion. 2  constipation. 3  irritable bowel syndrome (IBS) â a common digestive condition, which can cause stomach cramps, bloating, diarrhoea and constipation. 4  coeliac disease â an intolerance to a protein called gluten, found in wheat, rye and barley.
List of causes of GAS. Following is a list of causes or underlying conditions (see also Misdiagnosis of underlying causes of GAS) that could possibly cause GAS includes: Air swallowing (aerophagia) - this causes more belching than flatulence; can occur from eating too fast, chewing gum, smoking, ill-fitted dentures, or other reasons.