Acetaminophen is a medication commonly used to alleviate fever and pain. Common brands include Tylenol(r), Percoset(r), aspirin free Excedrin(r) and various sinus, cold and flu medications. Dogs most commonly receive toxic amounts of acetaminophen because owners medicate them without consulting a veterinarian. They also consume tablets that are dropped on the floor or left lying around.Dogs are less sensitive to acetaminophen than cats. For example, a 50 pound dog would need to ingest over seven 500 mg tablets in order to suffer toxic effects. In the cat, one 250 mg acetaminophen tablet could be fatal.

In addition to severe liver failure, acetaminophen causes damage to red blood cells. These include:.....................

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http://www.petplace.com/drug-library/ac ... page1.aspx

Safety data for 4-acetamidophenol

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Ironically, considering ASPCA and cohort's position on acetaminophen poisoning, this PDF file put out by the ASPCA reads as follows:

"Acetaminophen is primarily eliminated by two major pathways: glucuronidation and sulfation. When these pathways are saturated or deficient, an alternative pathway breaks down the acetaminophen to a toxic metabolite called NAPQI a free radical that damages hemoglobin, red blood cells (RBCs), and, occasionally, kidney cells. Cats are deficient in glucuronidation and sulfation abilities and, therefore, more susceptible to acetaminophen toxicosis than dogs. Cats have been shown to produce signs of acetaminophen toxicosis at a dose as low as 10 mg/kg.

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