Zinc (pennies, nuts, bolts and zinc oxide cream) in Pets

One modern US penny holds about 2,440 mg of zinc and can destroy a small dog's red blood cells. Learn which coins and creams matter, the two phases of signs and what to do now.

What It Is

When metallic zinc sits in the acidic stomach it dissolves and is absorbed, damaging red blood cells (haemolysis), the pancreas, liver and kidneys. The Merck Veterinary Manual notes that US pennies minted since 1982 are 97.5% zinc, equivalent to about 2,440 mg of zinc per penny, which makes them a key source.

Where Pets Come Across It

Coins, especially US pennies from 1983 onwards (some 1982 coins too), galvanised nuts, bolts and staples, zinc pet-carrier hardware, tabletop game pieces, and zinc oxide creams such as nappy rash ointment and sunscreen.

Which Animals Are Affected

Dogs most often; puppies swallow coins. Birds are very susceptible because they chew galvanised cage wire. Cats are affected less often.

Published Toxic Dose

Merck does not give a single mg/kg threshold because absorption depends on how long the object stays in the stomach. A single penny can cause serious haemolysis in a small dog if it is not removed. Zinc oxide creams mostly cause vomiting because the zinc is poorly absorbed in that form. The calculator therefore does not grade zinc by dose.

Signs and How Soon They Appear

Merck describes vomiting and other gut signs that can develop within minutes to days, followed by a second phase hours to days later: lethargy, pale or yellow gums, red-brown urine, and organ damage. Removing the object is essential.

What to Do Right Now

Call your vet if your pet may have swallowed a coin or metal object; an X-ray shows coins easily. Do not induce vomiting at home. If your pet licked zinc oxide cream, wipe its mouth and call for advice; vomiting is common but serious poisoning from cream is uncommon.

Frequently Asked Questions

Sources and References

• Merck Veterinary Manual: Zinc Toxicosis in Animals
• Pet Poison Helpline: Zinc

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