Toxin
Cholecalciferol (Vitamin D Rodenticides)

Source
Quintox, True Grit Rampage, Ortho Rat-B-Gone, and cholecalciferol as a livestock feed additive. Vitamins contain Vitamin D, such as Viactiv. Cestrum diurnum (Day Jessamine) and Solanum malacoxylon plants also are a source of cholecalciferol.

General Information
Cholecalciferol poisoning can occur by ingestion of a pesticide, or in farm animals, by the ingestion of an overdose of a feed additive containing cholecalciferol. It causes a drastic increase in the calcium level, which causes heart problems and bleeding secondary to mineralization of the vessels, kidneys, stomach wall, and lungs. This mineralization can also cause kidney failure. This toxin is very lethal.

One IU of vitamin D3 is equivalent to 0.025 mcg of cholecalciferol.

Toxic Dose
Dogs: Symptoms may occur with as little as 1 mg per pound of body weight; deaths have occurred with 4 mg per pound of body weight.

Toxicity rarely occurs in cats.

The Vitamin D in vitamin supplements is not considered a risk for companion animals, even with massive ingestion.

Signs
Depression, lack of appetite, increase in drinking and urinating, heart rhythm abnormalities, increased blood pressure, weakness, vomiting and diarrhea which may have blood in it, seizures, and death.

Immediate Action
Induce vomiting and seek veterinary attention immediately.

Veterinary Care
General treatment: The induction of vomiting may be continued, gastric lavage is performed, and activated charcoal is administered.

Supportive treatment: The goal is to decrease serum calcium levels by increasing urine production through administering IV fluids. Prednisone and furosemide may also be used for their diuretic effects. Seizures are controlled and electrolyte and hydration imbalances are corrected. Decreasing the exposure to sunlight decreases conversion of cholecalciferol to active vitamin D by the skin.

Specific treatment: Calcitonin or biphosphonate pamidronate disodium are used to decrease the serum calcium level.

Treatment may be required for two or more weeks as the experimental elimination half-life is 19 days. A low calcium diet is given for a month and vitamin/mineral supplements are also discontinued during this time.

Prognosis
Poor, if symptoms are present.