Zinc Poisoning in Cats

Zinc poisoning in cats, also commonly known as zinc toxicity, occurs when the acidic environment of the stomach breaks down excess sources of zinc and converts them into zinc salts. These zinc salts are absorbed through the small intestine, causing a variety of systematic problems. While zinc in small amounts is a nutrient that is vital to many processes in your cat, it is the excessively large amounts that result in damage and harmful side effects. 

The symptoms of zinc Poisoning in your cat will depend on the levels of excess zinc in the system. In the case of mild zinc poisoning, general sickness or lethargy may be the only indication of a problem. As the levels of zinc rise in your cat, the symptoms will increase in quantity and severity. These may include:

• Disinterest in food
• Severe lethargy
• Diarrhea
• Vomiting
• Stomach pain
• Anemia
• Jaundice (yellowing of the eyes, skin or gums)
• Blood in the urine
• Kidney failure as condition progresses

Zinc poisoning typically occurs when your cat ingests metal or some plastic objects that contain high amounts of zinc. The acidic environment of the stomach breaks down the item and causes the release of zinc into your cat’s system. One of the most common sources of zinc poisoning comes from ingestion of pennies, which are mostly made up of zinc. Young cats are also more prone to zinc poisoning due to the tendency of younger kittens to ingest foreign objects. The types of objects your cat may ingest that contain large amounts of zinc may include:

• Pennies made since 1983
• Bolts, nuts or other metal fasteners from pet carriers
• Certain children’s toys or figurines
• Nails
• Zinc lozenges (for humans)
• Jewelry
• Board game pieces
• Certain lotions or creams containing high amounts of zinc

A diagnosis of zinc Poisoning in your cat will begin with a thorough physical examination by your veterinarian. It will be important that you provide your vet a history of the progression of any symptoms, including timelines for escalation of severity of symptoms or appearance of new symptoms.

After the exam, your vet may order several laboratory tests. The first will be a complete blood profile, including a test for hemolytic anemia, which is a symptom of zinc poisoning. Your vet will also order a urinalysis to evaluate kidney function and to determine the presence of red blood cells in the urine. A blood test involves a simple blood draw using a basic needle method. A urinalysis may involve a urine collection while your cat is relieving themselves or, potentially, a needle withdrawal of urine directly from your cat’s bladder. 

Finally, your vet will order imaging in order to determine the presence of zinc-containing foreign objects in your cat’s stomach or digestive tract. This will be the definitive diagnosis of source of zinc poisoning. Your cat will need to be mildly sedated or anesthetized, depending on their level of anxiety, in order to obtain the best quality images possible.

Treatment of Zinc Poisoning in your cat will involve several phases. The source of zinc contamination will need to be removed and then treatment can begin in order to rectify the effects of zinc poisoning in your cat.

Removal of Zinc Contamination

After imaging has identified the presence of the foreign object that is releasing Zinc into your cat’s system, your vet will recommend a course of treatment to remove the item. Various procedures to do this may include inducing vomiting, endoscopy (in which a tube is sent down your cat’s throat with a small claw device to grab and remove the object) or potentially, surgical intervention. For both endoscopy and surgery, your cat will need to be put under anesthesia. In the case of induced vomiting, your cat may need to be monitored for potential aspiration pneumonia. 

Countering the Effects of Zinc Poisoning

After the zinc-containing foreign object is removed from your cat’s system, your vet will take steps to lower zinc levels in the blood and urine and to also counter any existing effects of zinc toxicity. These treatments will include administering subcutaneous fluids and medicines that lower acidity in the stomach, which prevents absorption of zinc into the system.

With timely treatment, including removal of the zinc-containing foreign object and reduction of zinc levels in the bloodstream, your cat’s prognosis for recovery is very good. Reduction of symptoms will begin immediately, and in all but the most severe cases, your cat will be able to return to a normal lifestyle almost immediately. Post-surgical care will be needed if the object was removed via this method. In cases of prolonged zinc exposure or delayed treatment, your cat may need kidney support for varying lengths of time.