What Is Deadly to Cats?

Over-the-counter analgesics such as acetaminophen, aspirin and ibuprofen may relieve aches and pains in humans but can prove fatal in felines. As few as two extra-strength acetaminophen pills in a 24-hour period can cause death in a cat, warns the American Animal Hospital Association. Aspirin is used in small doses to treat pain and fever in cats, but prolonged use can lead to life-threatening toxicity. Non-steroidal anti-inflammatory drugs such as ibuprofen and naproxen have been known to cause kidney damage in cats. Also poisonous are the decongestant pseudoephedrine, the muscle relaxant baclofen and drugs used to treat attention deficit hyperactivity disorder in humans.

Sharing may be caring, but not when it comes to cats and chocolate. All types of chocolate, as well as coffee, tea and other caffeinated products, contain substances known as methylxanthines that can cause abnormal heart rhythm, seizures and death in cats. In large amounts, garlic and onions, whether raw, cooked or in powdered form, can cause life-threatening anemia in felines. Ethanol, found in alcoholic beverages, can kill cats or put them into a coma, while raw yeast dough can lead to a rupturing of the stomach and intestines. Mushrooms, macadamia nuts, grapes and raisins are also toxic to cats.

Keep your kitty away from any type of lily, as even a few bites of any member of the Lilium spp. genus can lead to fatal kidney damage. Sago palm is also extremely toxic to cats, as it can cause liver failure. Azaleas and other members of the rhododendron family contain substances called grayantoxins that when ingested can result in a fatal collapse of the cat's cardiovascular system. Other plants to avoid include tulips (the bulbs are toxic), castor bean, chrysanthemums, autumn crocus and oleander.

Antifreeze, which cats find appealing, is a common cause of poisoning in felines, according to the Cornell University Department of Animal Science; even a teaspoon can be lethal. Common mouse poisons such as sodium fluoroacetate, cholecalciferol and those containing anticoagulants can also lead to death in cats, whether they ingest it directly or eat a contaminated rodent. Amitraz, an insecticide used on tick collars for dogs, is also highly toxic to cats.