Not all labs use the same range. Obtain a copy of your labs which should indicate the specific ranges. My current range is AST 10-40, ALT <36. A previous lab had AST 15-50 and ALT 5-50.
Drinking is a likely cause, but he should have a simple blood test to screen for hepatitis a, b and c. Depending how the tests come out, you might consider a liver ultrasound and biopsy. If possible, see a doctor that specializes in diseases of the liver to guide you. Try and take care of it now before things get worse. Normal range: AST(2-50),ALT (2-60)
-- Jim
http://www.fhea.com/cp/chapter8.htm here is a link i was told if ast is higher then alt its from drinking