Arsenic Poisoning in Cats

What is arsenic poisoning?

Arsenic poisoning is the accidental ingestion, skin contact, or inhalation of products containing a toxic dose of arsenic. Arsenic is a metal-like substance found naturally in rocks, soil, and water, but usually in very small, harmless amounts.

Arsenic is also used in commercial products and practices, such as wood preservation, pesticides, and fuels. Since the 1960s, using arsenic in commercial products and practices has declined, but it has not been eliminated. Today, the most common cause of arsenic poisoning in cats is ingestion of ant baits that contain arsenic.

What causes arsenic poisoning?

The toxic dose of arsenic can vary greatly depending on the form of arsenic, the animal species, and the health status of the animal. Cats and humans are the most susceptible to arsenic poisoning. Weak, debilitated, and dehydrated animals are more susceptible than normal, healthy animals.

Once absorbed by the body, arsenic travels to all the organs such as the liver, spleen, kidneys, lungs, and gastrointestinal tract. Once there, it mainly affects the vascular system (blood vessels), leading to swelling and bleeding in the organs.

What are the clinical signs of arsenic poisoning?

The clinical signs of sudden arsenic poisoning can vary depending on the dose. Clinical signs can include abdominal pain, salivation, vomiting, diarrhea, staggering, weakness, rapid weak pulse, lethargy, low body temperature, collapse, and death. If arsenic exposure occurs on the skin, effects such as blisters, swelling, cracking, bleeding, and infections can occur.

Long-term or chronic exposure to arsenic can cause weight loss due to decreased appetite, and nerve damage.

How is arsenic poisoning diagnosed?

Arsenic poisoning is diagnosed via history and clinical signs consistent with arsenic poisoning. Chemical analysis of the urine, liver or kidney biopsies, or gastrointestinal contents may be performed. Blood is not as useful for arsenic exposure because arsenic is cleared from the blood quickly. Hair samples may be helpful in testing for long-term exposure.

How is arsenic poisoning treated?

Arsenic poisoning treatment may vary depending on the type and time of poisoning. If your cat is not showing symptoms and the arsenic was ingested within 4 hours of examination, then vomit induction may be effective. Gastric lavage (flushing of the stomach) may be considered, but should be performed with caution. Activated charcoal is not helpful in cases of metal poisonings.

Chelation (binding) can also be useful in arsenic poisoning cases. Two types of chelating compounds are commonly used: dimercaprol (BAL) and succimer (DMSA). BAL itself is toxic, but if dosed appropriately, it can treat arsenic poisoning with few toxic effects. DMSA is less toxic, but it is less effective.

Supportive therapy is a crucial part of treating arsenic poisoning. Aggressive fluid therapy and rehydration is necessary and helps the body to remove arsenic from the body. Other supportive therapy includes antibiotics for secondary infections, anti-vomiting and anti-diarrheal medications, and a bland diet.

What care will my cat require after treatment for arsenic poisoning?

Your veterinarian should monitor the kidneys, the liver, and the electrolytes during and after treatment. If your pet makes a full recovery, no further aftercare is needed.