7/27/2019 Toxic Hepatitis and Drug
1/3
TOXIC HEPATITIS AND DRUG-INDUCED HEPATITIS
Certain chemicals have toxic effects on the liver and when taken
by mouth or injected
parenterally produce acute liver cell necrosis, or toxic
hepatitis. The chemicals mostcommonly implicated in this disease
are carbon tetrachloride, phosphorus, chloroform,
and gold compounds. These substances are true hepatotoxins. Many
medications may
induce hepatitis but and sensitizing rather than toxic. The
result, drug-inducedhepatitis, is similar to acute viral hepatitis;
however, parenchymal destruction tends tobe more extensive. Some
examples of medications that can lead to hepatitis are
isoniazid, halothane, acetaminophen, and certain antibiotics,
antimetabolites, and
anesthetic agents.
TOXIC HEPATITIS: MANIFESTATIONS AND MANAGEMENT
Toxic hepatitis resembles viral hepatitis in onset. Obtaining a
history of exposure to
hepatotoxic chemicals, medications, or other agents assists in
early initiation of
treatment and removal of the offending agent. Anorexia, nausea,
and vomiting are the
usual symptoms; jaundice and hepatomegaly are noted on physical
assessment.Symptoms are more intense for the more severely toxic
patient. Recovery from acute
toxic hepatitis is rapid if the hepatotoxin is identified early
and removed or if exposure
to the agent has been limited. Recovery, however, is unlikely if
there is a prolongedperiod between exposure and onset of symptoms.
There are no effective antidotes. The
fever rises; the patient becomes very toxic and prostrated.
Vomiting may be persistent,
with the emesis containing blood. Clotting abnormalities may be
severe, andhemorrhages may appear under the skin. The severe
gastrointestinal symptoms may
lead to vascular collapse. Delirium, coma, and convulsions
develop, and within a few
days the patient usually dies of fulminant hepatic failure.
Short of liver transplantation,few treatment options are
available.
Therapy is directed toward restoring and maintaining fluid and
electrolyte balance,blood replacement, and provision of comfort and
supportive measures. A few patients
recover from acute toxic hepatitis only to develop chronic liver
disease. In the eventthat the liver heals, there may be scarring,
followed by postnecrotic cirrhosis.
DRUG-INDUCED HEPATITIS: MANIFESTATIONS AND MANAGEMENT
Medication-induced hepatitis is responsible for up to 25% of
cases of fulminant
hepatic failure in the United States. Manifestations of
sensitivity to a medication mayoccur on the first day of its use or
not until several months later, depending on the
medication. Usually, the onset is abrupt, with chills, fever,
rash, pruritis, arthralgia,
anorexia, and nausea. Later, there may be jaundice and dark
urine and an enlarged andtender liver. When the offending
medication is withdrawn, symptoms may gradually
subside. Reactions may be severe, however, and even fatal, even
though the
medication is stopped. If fever, rash, or pruritis occurs from
any medication, its use
should be stopped immediately.
Although any medication can affect liver function, those most
commonly associated
with liver injury include but are not limited to anesthetic
agents, medications used to
trat rheumatic and musculoskeletal disease, antidepressants,
psychotropic medications,
http://000info.com/?go=drughttp://go-all.com/?go=drughttp://get-access.com/?go=drughttp://000info.com/?go=drughttp://go-all.com/?go=drughttp://get-access.com/?go=drug
