User:Viswa

Toxins & Poisons: Phenacetin is metabolized to acetaminophen. Acetammophen is metabolized by enzymes of the cytochrome P-450 series to intermediate products: nonreactive glucuronides and sulfates (which are conjugated and eliminated in the urine), and reactive metabolites, which are metabolized with glutathione to nontoxic mercapturic acid (which is eliminated). If the toxic metabolites accumulate as a result of insufficient glucuronide or sulfate metabolism or insufficient glutathione, they are converted to toxic macromolecules that directly cause cellular death. Cats lack glucuronyl transferase and inefficiently form glucuronic acid and sulfate conjugates, leaving more acetaminophen or phenacetin to be metabolized to toxic metabolites. The glutathione stores are rapidly depleted in cats, leaving a large amount of toxic metabolites. Methemoglobinernia occurs.