Liver tests such as AST and ALT can be raised without there being any symptoms. They are usually due to a fatty infiltration in the liver. The commonest causes of fat in the liver are overweight, diabetes or, of course, alcohol. Some drugs can also cause this, as can some viruses. However, if all the other tests are normal - then I suggest you try a period of losing weight and stop drinking. Also check the tablets you are taking. If the blood tests have not returned to normal in 3-6 months - then you should ask a doctor.