Zinc Poisoning in Cats

American pennies made after 1982 contain almost 98% zinc, which is enough to be fatal to a cat. Swallowed pennies tend not to pass through the digestive tract and sit in the stomach. They begin to break down from the stomach acids and release zinc salts that absorb and deposit into vital organs. This can become fatal if the penny is not removed via surgery or endoscopy.

Outside of pennies as a source of exposure, ingestion of items or products with a lower concentration of zinc carry a much better prognosis, and most cats recover within 3-4 days of diagnosis and treatment.

While zinc toxicosis in cats is very rare due to their discretion in eating abnormal items, it can be a serious condition that can lead to severe symptoms and even death. If a cat is witnessed swallowing a penny, this requires immediate veterinary intervention.

Higher doses of zinc, or items that have been ingested containing zinc that have not left the stomach will begin to leach salts and more serious secondary symptoms and conditions develop.

Most cats are not at risk of zinc poisoning because cats are usually discriminating eaters. Items containing zinc include:

• Pennies (made after 1982)
• Zippers
• Jewelry
• Screws and nuts on pet carriers
• Diaper rash cream
• Sunscreen
• Prenatal vitamins
• Zinc coated christmas tinsel
• Other supplements, creams, or items that contains zinc

Zinc toxicosis is caused by ingestion of a toxic amount of zinc. Zinc is digested by the stomach into zinc salts which then travel through the bloodstream and are deposited in vital organs. The exact mechanism of poisoning is not fully understood, but toxic levels of zinc lead to gastrointestinal symptoms and breakdown of red blood cells.

Symptoms of zinc toxicity vary depending on how much zinc has been ingested, and whether the source remains within the body (in the case of swallowing a penny).

Clinical signs arising after ingestion of lower doses of zinc are mostly gastrointestinal in nature.

Unless ingestion of an item containing zinc has been witnessed, it is difficult to determine the cause of symptoms, especially since initial symptoms are ambiguous.

Cats showing symptoms of GI upset should be closely monitored. Diagnosis can be made by a mixture of history and diagnostic tests, including:

• Bloodwork
• Urinalysis
• X-rays

Treatment for zinc toxicity includes removal of the ingested item and supportive care, including antacids, intravenous fluids, and blood transfusions. Removal of the item may be endoscopic, surgical, or through induction of vomiting.

Note: induction of vomiting should always be performed by a veterinarian. There is no safe way to induce vomiting at home.

Depending on the severity of toxicity and promptness of diagnosis and treatment, cats typically recover within 48-72 hours. In rare cases, the condition can be fatal. Fatal cases usually occur when ingestion of a penny is unknown and symptoms are not identified promptly, resulting in delayed diagnosis and treatment.

While cats do not eat foreign objects nearly as often as dogs, zinc-containing supplements such as gummies may be tempting to eat. Prevention of zinc toxicity in cats involves ensuring items containing zinc are out of reach. It is not contagious.

Zinc toxicity is very rare in cats.

• Immediate surgical or endoscopic removal of the ingested item (if applicable)
• Intravenous fluids
• Antacids
• Blood transfusions