Anticoagulant rat and mouse poisons are the most commonly used household poisons. These products account for a large number of accidental poisonings in cats and dogs. Anticoagulants block the synthesis of vitamin K-dependent coagulation factors, which are essential for normal blood clotting.
Observable signs of poisoning do not occur until several days after ingestion. The cat may become weak and pale from blood loss, have nosebleeds, vomit blood, have rectal bleeding, develop hematomas and bruises beneath the skin, or have hemorrhages beneath the gums. The cat may be found dead from bleeding into the chest or abdomen.
There are two generations of anticoagulants, both in current use.
The first generation anticoagulants are cumulative poisons that require multiple feedings over several days to kill the rodent. These poisons contain the anticoagulants warfarin and hydroxycoumarin.
Second-generation anticoagulants contain bromadiolone and brodifacoum, poisons that are 5 to 2 times more toxic than warfarin and hydroxycoumarin. These products are more dangerous to pets and are capable of killing rodents after a single feeding. It is possible for a cat to be poisoned by eating a dead rodent with residual poison in its stomach.
Closely related to the second-generation anticoagulants are the long-acting anticoagulants of the indanedione class (pindone, diphacinone, diphenadione, and chlorphacinone), which are extremely toxic.
Seek immediate veterinary help and, if at all possible, bring in the product container so the veterinarian can identify the poison. This is important, because treatment depends on whether the poison was a first- or secondgeneration anticoagulant. With observed or suspected recent ingestion, induce vomiting.
Treatment of spontaneous bleeding caused by all anticoagulants involves your veterinarian administering fresh whole blood or frozen plasma in amounts determined by the rate and volume of blood loss. Vitamin Kl is a specific antidote. It is given by subcutaneous injection and repeated subcutaneously or orally as necessary until clotting time returns to normal. With first-generation anticoagulants, this often occurs within a week. With long-acting anticoagulants, treatment takes up to a month because of the length of time the poison remains in the cat’s system.
Hypercalcemic agents are poisons that contain vitamin D (cholecalciferol) as their effective agent. Cholecalciferol poisons work by raising the calcium content in blood serum to toxic levels, eventually producing cardiac arrhythmias and death. They are becoming increasingly popular because rodents do not develop resistance to them. Cats who eat poisoned rodents may develop toxicity, but in most cases, the cat must eat the poison itself to become ill.
In cats, signs of hypercalcemia appear 8 to 6 hours after ingesting the poison. The signs include thirst and frequent urination, vomiting, generalized weakness, muscle twitching, seizures, and, finally, death. Among survivors, the effects of an elevated serum calcium may persist for weeks.
If you suspect your cat has ingested one of these poisons within the past four hours, induce vomiting and notify your veterinarian. Veterinary treatment involves correcting the fluid and electrolyte imbalances and lowering calcium levels using diuretics, prednisone, oral phosphorus binders, and a low-calcium prescription diet.
For more cat poisoning symptoms, treatments for minor poisoning, and phone numbers for 24 hour poison control hotlines visit http://www.2cathealth.com/cat-poisoning-symptoms.html