In general, dogs are more likely to intentionally eat something poisonous like chocolate or sweet-smelling antifreeze; cats are more likely to walk through something toxic and later ingest it when grooming.
The symptoms of poisoning depend on the kind of poison, the type of exposure (internal or external), the amount of exposure, and the particular pet. Some poisons, like flea-product toxicity, can develop symptoms within twenty minutes. Others may take hours to show.
Poisoning is an emergency that needs immediate veterinary attention — be sure to bring along whatever it is your pet has eaten. Many poisons have very specific antidotes.
You can help give your pet a fighting chance with some first aid treatments.
If your pet has swallowed something poisonous and is still conscious and in control of himself, the best thing you can do is make him vomit. Feed your pet a small meal to help dilute the poison and make it easier to induce vomiting. Dogs respond well to 3% hydrogen peroxide — about a teaspoon for every ten pounds your pet weighs. Use an eyedropper or turkey baster to squirt the liquid on to the back of your pet’s tongue.
DO NOT induce vomiting if your pet has swallowed a caustic poison like bleach or ammonia that will burn the mouth and throat or a petroleum product that can go into the lungs and cause serious damage. Pets generally won’t swallow a caustic poison, because it burns the mouth and throat. However, if you suspect he has swallowed a caustic poison, encourage him to drink water to dilute the poison and rinse out his mouth. Milk can also coat and protect the stomach. If your pet won’t drink, you can use a water bottle to spritz milk or water into his mouth.
If you cannot get to a veterinarian quickly, you can call the ASPCA Animal Poison Control Center at 1-888-426-4435 if you have a major credit card available or 1-900-443-0000 to bill the call to your phone bill. You can also call the National Animal Poison Control Center at 1-800-548-2423 if you have a credit card and 1-900-680-0000 if you want to bill the call to your phone bill. Your local poison control center may also have information about pet poisoning, but don’t count on them unless you have no other options.