Zinc Poisoning in Pets

Zinc is an essential mineral needed for DNA production, growth, wound healing, and immune function. Since zinc is not made in the body, it must be consumed in the diet. The body requires very small amounts of zinc and ingesting too much can cause poisoning.

Zinc is commonly found in metal objects, including nuts, bolts, zippers, jewelry, galvanized metal, nails, and board game pieces. Ointments, such as diaper rash creams and sunscreen, may contain large amounts of zinc. Because of its effects on the immune system, zinc is commonly available in vitamin supplements and over-the-counter cold remedies. In the United States, pennies made after 1982 are made with a zinc core covered in copper plating. Ingestion of these pennies is one of the most common causes of zinc poisoning in pets. 

How much zinc is poisonous to pets? 

The amount of zinc required to cause poisoning depends upon the pet’s size, the form of zinc ingested, and how much was ingested. Some forms of zinc are more readily absorbed than others. A one-time ingestion of zinc oxide cream typically only causes stomach upset. However, repeated ingestion of these ointments over days to weeks can cause poisoning, especially with more concentrated products. 

Ingestion of pennies and other metallic objects is more likely to cause poisoning, especially in smaller pets where it may be more difficult for the object to move out of the stomach. Ingesting as few as 1–2 pennies can result in zinc poisoning. Simply chewing on galvanized metal wire cages or metal toys has caused zinc poisoning in birds. 

What are the signs of zinc poisoning? 

Zinc initially causes irritation of the gastrointestinal tract, and most pets with zinc poisoning develop stomach upset, depression, stomach ulcers, and lack of appetite. After the initial signs, zinc poisoning causes a low red blood cell count (anemia) by damaging the red blood cells. This results in weakness, pale gums, increased heart rate, respiratory rate and effort, yellow discoloration of the eyes or skin (icterus), and red or dark yellow/orange discoloration of the urine. Pets may also suffer organ damage, weight loss, and abdominal pain. 

If you witness or suspect your pet of ingesting any zinc-containing product, consult a veterinarian or Pet Poison Helpline, a 24/7 animal poison control center, at 1-800-213-6680, to assess the risk of poisoning. 

How is zinc poisoning treated? 

As with all poisoning cases, early intervention is key to successful treatment. Call your veterinarian or Pet Poison Helpline as soon as you realize your pet has been exposed to zinc. Treatment depends on the form of zinc (metallic or non-metallic) and the severity of the pets’ signs. Supportive therapy includes fluid support and medications to treat the pet’s clinical signs. Metallic objects often require surgical or endoscopic removal. For adequate treatment and observation, be prepared to have your pet stay in the hospital through the day with mild cases and for a few days in more severe cases. 

What is the prognosis for zinc poisoning? 

The outcome of zinc poisoning depends on many factors, including the type of zinc and amount ingested, time to treatment, and severity of the pets’ signs. With early treatment, pets are less likely to develop long-term effects. Most pets that ingest zinc ointment one time will recover fully with appropriate supportive care. Prompt treatment and early removal of any metal objects ingested decrease the risk of serious effects. 

Most pets recover within 2–3 days of removing the source of zinc. Permanent organ damage or death may occur in pets with severe signs or delayed treatment. Contact a veterinarian or Pet Poison Helpline (1-800-213-6680) immediately if zinc ingestion occurs to improve the likelihood of proper treatment and increase the chance of a full recovery.

Pet Poison Helpline, an animal poison control center based out of Minneapolis, MN, is available 24/7 for pet owners and veterinary professionals that require assistance treating a potentially poisoned pet. The staff provides treatment advice for poisoning cases of all species, including dogs, cats, birds, small mammals, large animals, and exotic species. As the most cost-effective option for animal poison control care, Pet Poison Helpline’s per-incident fee includes follow-up consultations for the duration of the poison case. Pet Poison Helpline is available in North America by calling 800-213-6680. Additional information can be found online at www.petpoisonhelpline.com.