Rodenticides can be helpful at keeping unwanted mice and rats out of our dwellings, but if our pets find a hidden stash they can become devastating killers. Most of the commonly used rodenticides are anti-coagulants. This means that they affect the animal's ability to clot blood. For you "scientific types"...their mode of action is to render the body unable to convert Vitamin K (ingested in the diet) into its active form of Vitamin K-1. Vitamin K-1 is responsible for regulating
what is called the coagulation cascade. Without the proper functioning of
this cascade, platelets are not able to form effective clots, eventually leading to spontaneous bleeding (either externally or internally). Rodenticide toxicity is not an immediate toxicity. It usually takes about 3-5 days before clinical signs develop (related to active bleeding and anemia). However, it is best to treat this toxicity as soon as possible (before clinical signs develop) for a more successful outcome. Initial treatment will usually include induction of vomiting to get as much of the product out of the stomach (assuming the ingestion has occurred recently). Once the stomach is emptied, an Activated Charcoal product is administered orally to try and absorb/bind up any of the product that has made it out of the stomach and into the intestines. Finally, the pet is started on an oral supplement of the
active form of Vitamin K-1 for a period of 3-4 weeks depending on the specific
product. IF active bleeding has already started at the time of treatment, it is usually necessary to give either a plasma or whole blood transfusion to stop the bleeding and reverse the effects of the associated anemia. It is VERY helpful for your Veterinary Health Care Team if you can have the product information
(especially the name of the active ingredient) available. There are some rodenticides that are not anti-coagulant in nature and therefore require an entirely different treatment approach.
Antifreeze or Ethylene Glycol Toxicity is another very common emergency
presentation. In addition to the traditional use of Ethylene Glycol in our car engines, it is also found in some solvents, rust removers, windshield wiper fluids and even in those decorative "snow globes"! It is actually the metabolite (or break-down product) that is toxic to our pets. This metabolite will cause a severe metabolic acidosis and acute kidney failure. Many owners initially report that their pet is walking "like it is drunk"...this can rapidly progress to anorexia, vomiting, lethargy, seizures, coma and eventually death. Ethylene Glycol Toxicity
can be broken down into three distinct phases. Phase 1 is the Neurologic Phase ("Drunken Phase") and usually occurs 30 minutes to 12 hours post-ingestion. Phase 2 is the Cardio-Respiratory Phase. During this phase panting and a fast heart rate are noted and usually occurs 12-24 hours post ingestion. Phase 3 is the Renal or Kidney Phase. This is when permanent damage to the kidneys is occurring, leading to a decrease in urine production and a buildup of toxins within the blood
stream. This final phase of poisoning typically occurs 24-72 hours post ingestion. There is an Ethylene Glycol Test Kit available for your Veterinarian to use on your pet's blood, but this test is only most accurate 1-4 hours post ingestion, is often difficult to interpret and is not very reliable after 12 hours post ingestion. Treatment needs to be started ASAP if there is any hope of success... once the advanced clinical signs begin it is highly unlikely that the patient will survive
treatment. This is one of the poisonings that has a specific antidote 4-Methylpyrazole or 4-MP) for dogs that have ingested Ethylene Glycol. This 4-MP is the best treatment, but can be costly... especially in larger dogs. It is ideal to start treatment within the first 8 hours after ingestion, but may be helpful even up to 24-36 hours post ingestion. The antidote works by blocking the metabolism of Ethylene Glycol into its toxic metabolite. If the 4-MP treatment is deemed to be too costly (or if the patient is a cat) an alternate (but less effective)
treatment option is the administration of ethanol (usually in the form of vodka)
intravenously and intensive in-hospital supportive care. If presented early, induction of vomiting and the administration of activated charcoal may also be helpful.
Although with the development of many newer (and safer) flea treatment products we are seeing less and less Organophosphate Toxicities... occasionally a case will still come through our front door. Organophosphates are a type of chemical/pesticide used in certain insecticides, older flea sprays, flea dips and some Over-The-Counter (OTC) Flea Spot-On Products. They can affect dogs, but cats seem to have an increased sensitivity to these products. Therefore, we do
not recommend the routine use of any OTC flea products on your cats without a specific recommendation from your veterinarian. A common error that we see is toxicity from accidentally applying a dog flea product onto a cat. The typical presentation is a twitching cat that becomes extremely cold and lethargic. If left untreated this can progress to seizures, coma, respiratory failure and eventually death. This toxicity is usually treated successfully with a combination of medicated baths to remove as much of the toxic substance as possible, IV fluid support and medications to control the muscle twitching and/or seizures while the body recovers from the poisoning.
While any medication has the potential to cause problems for your pet, the most common culprit we see is the class of drug referred to as the Non-Steroidal Anti-Inflammatory Drugs (NSAIDs). These are the medications that include Motrin (Ibuprofen) and Tylenol (Acetaminophen) that you and I routinely use for aches, pains, fever and inflammation. However, to our pets they can be a ticking time bomb! Ibuprofen has a very narrow margin of safety in pets, so it should never be recommended for routine use at home. Ingestion can lead to acute vomiting and gastric ulceration/perforation within 1-4 hours. Higher doses can result in kidney damage and acute kidney failure within 1-5 days. Acetaminophen toxicity is due to a metabolite (break-down product) that leads to liver cell damage/liver failure and red blood cell damage/anemia. Dogs seem to be more sensitive to the liver effects---progressive lethargy, vomiting, abdominal pain, icterus/jaundice and death within 2-5 days. Cats seem to be more sensitive to the red blood
cell effects---lethargy, weakness, hypothermia, brown or blue colored mucous
membranes (including the gums), dark colored blood and urine...all of which can
occur within 1-2 hours of ingestion and death can occur within as little as 24-36 hours! If your pet has accidentally ingested either of these (or any prescription or non-prescription medication) you should contact your Veterinarian immediately for instructions. Again, it is always helpful to have the drug name (Trade Name or Generic), strength of medication (usually in milligrams/mgs) and suspected number of pills ingested readily available for the Veterinary Health Care Team.
Finally, there are many common household and garden plants that have the potential to be toxic to our pets. But one of the most serious is the Lily. The Easter Lily, Tiger Lily, Japanese Show Lily, some species of Day Lily and certain other members of the Liliaceae family can cause kidney failure in cats. All parts of these lilies (flowers, leaves and bulbs) are considered toxic to cats and consuming even tiny amounts can be life threatening to your cat. If a suspected ingestion has occurred, immediate evaluation and treatment by your Veterinarian is warranted.
For a full list of Household Hazards, Poisonous Plants and Frequently Asked Poisoning Questions, visit the ASPCA's Animal Poison Control Center at http://www.aspca.org/pet-care/poison-control/ . Keep an eye out for our next blog where we will discuss Foods that can be harmful to your pets.