My doctor wants me to have my liver enzymes checked in 4 weeks ast was 54,alt 21.asp normal negative for hep c, is 4 weeks long enough for ast to decrease? what can be done to lower ast? i dont drink alcohol or take tylenol. bmi 22. all labs normal?

Yes, the half-life (time to drecrease by half) in the circulation is about 47 hours for ALT and 17 hours for AST; So 4 weeks is ok. having elevated AST is not proof of a medical problem. It is possible for healthy people with proper liver function to have an AST level outside the normal range, which can occur based on individual factors like age, sex, race, diet, exercise, or medications

Four weeks should be long enough. A next step would be to ask your primary care provider to refer you to a hepatologist, with the request that a lipid panel be ordered along with liver function tests. Because of your low BMI, specific disease processes that should be evaluated would include non-alcoholic fatty liver disease (NAFLD), primary biliary cirrhosis, and primary sclerosing cholangitis.