Internal Medicine

P1: RLJ/OZN P2: KUF

0521779407-D-01 CUNY1086/Karliner 0 521 77940 7 June 13, 2007 7:41

Drug and Toxin-Induced Liver Diseases Drug Eruptions 503

specific therapy

■acetaminophen: N-acetylcysteine (Mucomyst): 140 mg/kg orally fol-

lowed by 70 mg/kg orally every 4 hours for an additional 17 doses

■liver transplantation:

➣indications for FHF due to acetaminophen:

pH <7.3 irrespective of stage of encephalopathy, or

INR >6.5 and serum Cr >3.4 mg/dL in patients with stage 3 or

4 encephalopathy

➣indications for FHF due to other drug reaction (or viral hepatitis):

INR >6.5, or

any 3 or the following:

etiology: drug reaction or non-A, non-B hepatitis

age: <10 or >40 years

duration of jaundice before encephalopathy >7 days

serum bilirubin >17.6 mg/dL

INR > 3.5

follow-up

■surveillance for abnormal liver tests: important in chronic use of thera-

peutic agents with known and/or dose-dependent hepatotoxicity

■methotrexate: a cumulative dose of 1.5 g is associated with significant

liver disease; liver biopsy every 2 g is performed by some although

its benefit is uncertain

complications and prognosis

■wide spectrum of hepatotoxicity: subclinical liver disease with mildly

abnormal liver function tests to fulminant hepatic failure requiring

liver transplantation

■acetaminophen: usually has good prognosis in the absence of under-

lying liver disease, chronic alcoholism, delayed administration of

antidote, extremes of age

■with the excepton of acetaminophen, drug and toxin-induced ful-

minant liver failure seldom recovers spontaneously

Drug Eruptions......................................

NEIL H. SHEAR, MD, FRCPC, FACP and JOHN R. SULLIVAN, MB, BS, FACD

REVISED BY NEIL H. SHEAR, MD, FRCPC, FACP

history & physical

History

■Drugs can induce, aggravate or cause eruptions that mimic a broad range

of skin disorders. Always consider, “Could this rash be drug-related?”