- Severe physical or medical illnesses such as AIDS, active hepatitis, significant hepatocellular injury as evidenced by elevated bilirubin levels (>1.3), or elevated levels (over 3.5x normal) of aspartate aminotransferase (AST), and serum glutamic-pyruvic transaminase (SGPT) after the required 3 days of abstinence, or severe renal disease, severe respiratory diseases or severe diarrhea with resulting metabolic acidosis, serum bicarbonate (< 20 milliequivalent (mEq)/L)