Cats are sensitive to many toxic agents, sometimes in ways unique to their species. Although cats are less likely than dogs to expose themselves through "curious" ingestions, cats do have more of a tendency to nibble on deadly agents. Cats are also able to jump to high places and squeeze into small spaces that are out of reach to dogs, children and even adults! Lastly, because of their need to groom, cats with skin exposure to hazardous chemicals are likely to receive an oral dose as well. In this article we describe 10 common household hazards that are dangerous to cats. The products listed below have been selected based on the most frequent feline exposures reported to the ASPCA Animal Poison Control Center (APCC) over the last four years.

1-2. Canine topical treatments and other topical insecticides

Believe it or not, owners often accidentally apply dog flea and tick treatments on their cats. In some cases, cats have even developed signs of poisoning after being in close contact (sleeping near or grooming) with a dog that has recently been treated with a flea/tick topical medication. Initial signs of intoxication may appear within a few hours but can take 24 to 72 hour to show up. Full body tremors are the most common, though seizures may also occur.

Cats may also have an adverse reaction to topical insecticides specifically designed for cats. In general, topical flea control products applied according to the label directions do not cause problems. If signs such as irritation of the skin or hypersensitivity appear, wash the product off with a mild detergent. If a cat licks the applied product, hyper-salivation, agitation and occasionally vomiting, may develop. The best way to avoid any problems is to read the directions carefully and thoroughly before applying any topical medication or product on your cat.

3. Venlafazine

Venlafaxine (Effexor, Effexor XR-Wyeth) is an antidepressant available in tablets and capsules. Cats seem to be big fans of venlafazine and readily eat capsules containing the drug. Although this is not a common household drug it can cause serious illness if ingested. Clinical signs include dilated pupils, vomiting, tachypnea (rapid breathing), tachycardia (rapid heart rate), ataxia, and agitation. Signs generally begin within one to eight hours after ingesting the medication. The prognosis is good with timely treatment and close monitoring.

4. Glow sticks and jewelry

Glow sticks and jewelry are plastic bracelets, necklaces, and wands that contain a liquid that glows in the dark. The jewelry is popular throughout the summer, especially around the Fourth of July and at Halloween. Cats frequently bite into the jewelry, but due to the extremely unpleasant taste of the liquid chemical, they generally don't ingest more than a small amount. Almost immediately after biting into a piece of glow jewelry, a cat exhibits signs of a taste reaction, including hyper salivation, agitation, and, occasionally, vomiting. The behavioral changes are likely due to the cat's reacting to the unpleasant taste. A tasty treat such as milk, liquid from a tuna fish can, or other palatable food can ameliorate the taste reaction. Remove any liquid on the fur with a wet washcloth to prevent re-exposure. Since the liquid is designed to glow in the dark, it is easiest to identify the chemical on the cat in a darkened room.

5. Lilies

Though beautiful to look at, lilies can pose a threat to cats. While many plants are called lilies, cats can develop acute renal failure after ingesting Easter lilies, Stargazer lilies, Tiger lilies, Asiatic lilies, Oriental lilies and Day lilies. Within two to four hours after ingesting any part of the plant (including the pollen), vomiting and depression can occur. Often the cat seems to recover only to deteriorate rapidly about 24 to 72 hours after the exposure. The symptoms that appear include frequent urination, frequent drinking of water and more severe depression. The prognosis is good with prompt, aggressive treatment.

6. Liquid Potpourri

Who doesn't like a pleasant smelling house? Unfortunately, liquid potpourri, used for just that purpose, is hazardous to cats. Cats, ever the curious species, may lick the product from the container or from their fur if exposed to a spill. The liquid may contain high concentrations of detergents, essential oils or a combination of both. Clinical signs of ingestion include upset stomach, drooling, depression and hypotension. If skin or eye exposure occurs, skin irritation and ulceration along with severe corneal ulceration can occur.

7. NSAIDs - Non-Steroidal Anti-Inflammatory Drugs

Cats may be exposed to non-steroidal anti-inflammatory drugs (NSAIDs) either by owner administration or, more rarely, by self-ingestion. Although NSAIDs are a group of medications, the most common ones are carprofen (Rimadyl), ibuprofen, deracoxib, naproxen (Aleve), etodolac, meloxicam, and indomethacin. Ingestion of these NSAIDs can cause stomach upset, including vomiting, diarrhea, ulceration, bleeding and ulcer perforation. Acute renal failure, seizures and comas have been associated with higher doses. In general, cats have a low tolerance for NSAIDs. For example, cats are thought to be at least twice as sensitive to ibuprofen as dogs. Because of this sensitivity, most exposures require emergency, aggressive treatment.

8. Acetaminophen

Acetaminophen, most commonly known as Tylenol, is an over-the-counter medication used to relieve pain and reduce fevers. Most often, owners attempting to help relieve their cat's discomfort, wind up causing harm by administering acetaminophen as a pain reliever. As with NSAIDs, cats should never be given acetaminophen as a pain reliever. Specifically, acetaminophen breaks down into smaller pieces that bind to red blood cells and other tissue cells, resulting in the destruction of these cells. In other words, just one pill can cause significant tissue damage in cats. Signs of intoxication develop quickly and can include salivation, vomiting, weakness, abdominal pain and fluid build up (edema) in the face or paws.

9. Rodenticides (rat poison)

Poisons intended to kill rats, mice, gophers, moles and other pesky mammals are among the most common and deadly of household poisons. Since rodents and cats are all mammals, it makes sense that substances highly poisonous to mice, for example, would be just as lethal to cats. It cannot be stressed enough that rodenticides are highly toxic and any such poisons designed to kill small mammals need to be carefully stored away from curious kitties. Also, since cats can be natural rodent hunters, it would be wise to let nature take its course as opposed to exposing your cat to a deadly toxin.

While there are many categories of rodenticides, the most common poisoning seen in veterinary practice is that of the anti-coagulant kind. Anti-coagulant rodenticides have ingredient names like warfarin, fumarin, diphacinone, and bromadiolone. These poisons act by interfering with a cat's ability to utilize vitamin K. Without vitamin K, a cat's blood is unable to clot when necessary, which can ultimately cause severe blood loss, anemia, hemorrhage and death. Generally, clinical signs are not seen until three to five days after the cat has ingested the poison. Symptoms resulting from intoxication are weakness, difficulty breathing, pale mucous membranes, bruising and bleeding from the nose. Other types of rodenticides can cause neurological signs such as incoordination and seizures as well as cardiac failure.

If accidental ingestion of rat poison is suspected, contact your veterinarian immediately, even if your cat is showing no obvious signs of being ill. Be sure, if possible, to bring the poison container to the veterinary hospital in order to determine the specific rodenticide ingested. Early recognition is critical, as some toxicities can be treated successfully if caught early and treated appropriately.

10. Fertilizer

Spring and fall are the times to fertilize. Unfortunately, it is also the time for accidental poisoning. Cats, the perennial groomers, often lick their paws, especially after walking outdoors. Because fertilizers are usually a combination of ingredients, several toxic outcomes are possible. In general, the ingredients are poorly absorbed and most clinical signs are related to gastrointestinal irritation showing up as vomiting, hyper-salivation, diarrhea or fatigue. The best way to avoid illness or injury is to keep your cat inside while treating your lawn and wait a little bit before letting him or her out again.