1. alt/ast \> 5 times the upper limit of normal. 2. mortality within 12 hours of admission. 3. pregnancy. 4. anticipated transfer to another hospital within 24 hours. 5. allergy to any study medication commercial or public health assay in any specimen prior to randomization. 6. mechanically ventilated on admission

1. alt/ast \> 5 times the upper limit of normal. 2. mortality within 12 hours of admission. 3. pregnancy. 4. anticipated transfer to another hospital within 24 hours. 5. allergy to any study medication commercial or public health assay in any specimen prior to randomization. 6. mechanically ventilated on admission

alt/ast > 5 times the upper limit of normal. mortality within 12 hours of admission. pregnancy. anticipated transfer to another hospital within 24 hours. allergy to any study medication commercial or public health assay in any specimen prior to randomization. mechanically ventilated on admission

alt/ast > 5 times the upper limit of normal. mortality within 12 hours of admission. pregnancy. anticipated transfer to another hospital within 24 hours. allergy to any study medication commercial or public health assay in any specimen prior to randomization. mechanically ventilated on admission

1. alt/ast > 5 times the upper limit of normal. 2. mortality within 12 hours of admission. 3. pregnancy. 4. anticipated transfer to another hospital within 24 hours. 5. allergy to any study medication commercial or public health assay in any specimen prior to randomization. 6. mechanically ventilated on admission

1. alt/ast > 5 times the upper limit of normal. 2. mortality within 12 hours of admission. 3. pregnancy. 4. anticipated transfer to another hospital within 24 hours. 5. allergy to any study medication commercial or public health assay in any specimen prior to randomization. 6. mechanically ventilated on admission