STORY AT-A-GLANCE
- Pennies minted after 1982 pose a serious risk to pets because they’re made out of mostly (nearly 98%) zinc
- Once in your pet’s stomach, stomach acid will begin to corrode the penny and in so doing rapidly release zinc into your pet’s bloodstream
- Excess zinc exposure can destroy red blood cells and cause liver damage, kidney failure, heart failure and death
- If your pet eats a penny (even just one), seek emergency veterinary care immediately
- Other sources of zinc to keep out of your pet’s reach include human supplements, cold remedy lozenges, zinc oxide creams and ointments (such as sunscreen and diaper rash cream), and acne medications
Editor's Note: This article is a reprint. It was originally published July 30, 2016.
If you have pets in your home, be sure to be very careful where you store your loose change. A shiny, dirty (imagine all the smells) coin can be quickly gobbled up by pets — typically by dogs but also possibly by cats and birds.
Anytime a coin is eaten, there's a risk of potential problems, including intestinal blockage (this is especially true if a large number of coins are consumed). However, the even more urgent and potentially deadly issue isn't necessarily an obstruction, it's the toxic metal lurking in the coin, specifically certain pennies.
Pennies Minted After 1982 Can Kill Your Pet
Pennies minted after 1982 pose a serious risk to pets because they're made out of mostly (nearly 98%) zinc. Only the outer coating is copper (making up about 2.5% of the penny's metal). This is in sharp contrast to pennies minted prior to 1982, when they were made from about 95% copper.1
The switch to zinc is important for pet owners to be aware of, as it's toxic to pets when consumed in excess. Once in your pet's stomach, stomach acid will begin to corrode the coin and in so doing rapidly release zinc into his bloodstream.
This excess zinc exposure can destroy red blood cells and cause liver damage, kidney failure and heart failure.2 You may notice the following signs and symptoms:
- Weakness
- Anemia (pale gums)
- Vomiting
- Increased heart rate and breathing
- Discolored urine (pink, brown)
- Jaundiced gums
- Lack of appetite
- Collapse
- Death
One penny contains about 2,440 milligrams of zinc,3 and while it's unknown what the toxic zinc dose in dogs is, it's known that the longer a penny sits in your dog's stomach, the more zinc that will be systemically absorbed.4
Zinc inhibits the production of red blood cells and the longer the exposure to the zinc, the greater the damage to red blood cells. The problem is that many pet parents do not actually see their pet ingest the penny, and therefore may not associate the symptoms that follow with an ingested coin.
If your pet displays any of the symptoms noted above, seek veterinary attention immediately. An x-ray can reveal whether a metallic object such as a penny is in your dog's stomach. Laboratory tests to measure the levels of zinc in the pet's blood should also be run.
Just One Penny Can Fatally Poison Your Dog
Please don't assume that your pet must ingest an entire piggy bank to be in serious trouble. There are, sadly, many cases of dogs dying after ingesting just a single penny.
There are stories of hope as well, such as Jack, a Jack Russell terrier from New York City, who swallowed 111 pennies and survived after his veterinarian was able to surgically remove the coins.5
In Jack's case, vomiting was the initial symptom, which highlights why it's so important to seek veterinary care if your dog is vomiting or seems otherwise ill. The American Society for the Prevention of Cruelty to Animals (ASPCA) Animal Poison Control Center (APCC) highlighted another case of penny poisoning in a dog:6
" … [A] dog had been vomiting for three days and was suffering from anemia and elevated kidney values when his regular veterinarian called the APCC for help.
His owner had no idea if he'd eaten anything out of the ordinary, but the APCC suspected zinc toxicosis. Sure enough, x-rays revealed a metallic object in the stomach."
After the coin was surgically removed, this lucky dog made a full recovery after about 10 days. As mentioned, while dogs are most likely to be poisoned by pennies, even cats and larger pet birds can be at risk.
The easiest way to prevent this potentially deadly accident is to store your coins safely out of your pet's reach.
In addition, wild animals and zoo animals also suffer if they ingest pennies, so be careful about dropping coins outdoors and definitely avoid tossing pennies into fountains, ponds or zoo-animal habitats.
Other Items That Pose a Risk of Zinc Toxicity
In addition to pennies, animals can be poisoned if they consume other sources of zinc as well. Top risky items to watch out for include:
- Human vitamin and mineral supplements
- Cold remedy lozenges
- Zinc oxide creams and ointments (such as sunscreen and diaper rash cream)
- Acne medications
- Galvanized steel nuts and bolts (such as those found on pet crates)
- Tacks
- Zippers from clothing and luggage
- Batteries
- Board game pieces
If your pet ingests a zinc-containing item, it will need to be promptly removed. Surgery may be necessary or in some cases the item may be able to be removed non-surgically using an endoscope.
First, however, your pet must be stabilized. Initial efforts should be focused on treating dehydration, shock, and electrolyte imbalances, and increasing urine output. After that, supportive care will be necessary depending on the extent of zinc poisoning.
This may involve fluid therapy to help prevent kidney failure, blood transfusion in cases of severe anemia and more. Prevention is the best strategy here, so keep all zinc-containing objects away from your pets. Also, be sure you're not intentionally giving your pet extra zinc.
There is a rare skin condition called canine zinc-responsive dermatosis that occurs in some northern breed dogs. Some pet owners wrongly assume supplemental zinc will help with their pet's dry, flaky or allergic skin and begin supplying zinc pills, which can cause fatal toxicosis in some cases.
