Q:My neighbor said rat poison can be dangerous for dogs. We visit
my grandmother's farm sometimes, and she said she has rat poison in her barn. Our dogs run loose on the farm when we visit. Should I be worried if my dogs eat some rat poison?
A: It kills me to see a pet come into the hospital that may have been exposed to rat poison. The prognosis is always guarded at best. Unfortunately, from a recent case I learned that rat poisons, or rodenticides, are one of the Top 10 pet toxins listed by the ASPCA.
Toxicity is common in dogs because the poisons are either grain- or sugar-based and taste good to rodents and dogs alike. They come in pellets, blocks, granules or liquid forms and can be teal, blue, green or pink. If you suspect your dog has ingested even a little bit of rat poison, I would consider it an emergency. Grab the package information and go immediately to your veterinarian with your pet.
Your vet will need to know which type of poison the dog has ingested. There are several types on the market and all are deadly. The first and most common type of rodenticide acts as an anticoagulant. The active ingredient may be brodifacoum, warfarin or bromadiolone to name a few. It kills by interfering with the body's ability to recycle Vitamin K. Without Vitamin K, blood cannot clot and these animals will bleed to death internally.
Unfortunately, it may take up to seven days for the effect of the ingestion to manifest itself in your pet. It will become lethargic and stop eating. You may notice increased respiratory effort and pale lips and gums. Some dogs will have nosebleeds and pass blood in stool, urine and vomit later in the progression of the disease.
Another type of rodenticide is the bromethalins. They act by increasing the amount of sodium in cells. This causes water to flow into cells and cause them to swell, burst and die. This effect can be observed in any organ system of the body, but the central nervous system is most commonly affected. Signs of toxicity will appear over a one- to two-week period with small amounts of ingestion. Large amounts of ingestion are rapidly fatal.
A third type of rodenticide contains a class of chemicals called cholecalciferols. This leads to an increase in calcium in the body. Too much calcium leads to acute renal failure and cardiac abnormalities. These signs will not appear until 12 to 36 hours after ingestion and include increased water consumption and urination, vomiting, not eating and increased effort to breath.
The last type of rodenticides is available only to professionals and is not common. They include strychnine and zinc phosphide. Again, this is a very serious and potentially fatal exposure.