Tylenol (Acetaminophen) Toxicity

This medication commonly used in people can cause liver toxicity in dogs when given one to two tablets daily over several days.

Cats have a lower ability to metabolize this drug. A single dose of one half to one tablet can cause poisoning affecting the ability of red blood cells to carry oxygen. One extra strength tablet can be fatal.

This is one of the most common drug toxicity in cats.

It is seen considerably less frequent in dogs.

Clinical Signs

Signs may develop 1–4 hr after dosing and include:

Depression

Rapid breathing

Darkened mucous membranes-this reflects the inability of the red blood cells to carry oxygen in cats

Progressive depression

Facial swelling in cats

Salivation

Vomiting

Abdominal pain

Chocolate-colored urine especially in cats

Death

History of exposure is most important for differentiating from other diseases.

Diagnostic Tests

CBC/Biochemistry Profile /Urinalysis

Dogs—destruction of the liver; elevated liver test and jaundice in chronic cases

Treatment

Induce vomiting and place a stomach tube to evacuate the stomach is useful within 4–6 hr of ingestion

Activated charcoal

SAMe (S-adenoslmethionine)

N-acetylcysteine (Mucomyst)

A blood transfusion may be required

Fluid therapy is administered to maintain hydration and electrolyte balance

CLIENT EDUCATION

Clinically affected patients may be prolonged and expensive.
and that patients with liver injury may require prolonged and costly management.

PREVENTION/AVOIDANCE

Never give acetaminophen to cats

Give careful attention to the acetaminophen dose in dogs.

POSSIBLE COMPLICATIONS

Pets with affected livers may develop cirrhosis (scarring ) of the liver. This is a permanent disease.

EXPECTED COURSE AND PROGNOSIS

The prognosis is guarded due to damaged red blood cells and can be fatal.
Death can occur 18-24 hours after ingestion in cats and dogs can develop irreversible liver disease.

For more information call National Animal Poison Control: 900 680 0000