Zinc Toxicity and Poisoning in Dogs
Pennies are Poisonous?
Zinc Toxicity is a scary thing. Newer pennies are mostly made of zinc; ingesting few as one to three pennies can cause problems. Our little dog, aptly name Penny, ate 6 pennies and almost died. I'm writing this article as a warning to pet owners, and even parents, so they can identify the signs and symptoms of zinc toxicity and penny poisoning before it's too late.
Did you know pennies were toxic?
Our Little Lady's Little Problem
Penny, a beagle/cattle dog mix, has been obsessed with metal for as long as we've had her. She will gnaw on zippers and lick our metal coffee table, cabinet knobs, jewelry, and coins. She loves coins. This particular habit has been at best, our dog's funny quirk (e.g. licking women's jewelry while they're wearing it), and at worst, a nuisance (e.g. destroyed zippers on jackets). We had looked into potential nutritional reasons for her behavior, but we have her on premium food and she has no dietary deficiencies as she's had her blood checked before. Additionally, her littermate in a different household has the exact same obsession. Dog genes, I'm looking at you!
Penny has discovered and promptly eaten coins on about 3 separate occasions; every time she has thrown up the change like some kind of gross slot machine. We always thought the biggest danger with her coin obsession was the risk of it getting stuck in her intestines. While we suspected coins could be dangerous if caught in the digestive tract, we had no idea that pennies can cause serious damage to the body before they even get to the intestines.
Penny Ate a Penny
The recent incident occurred over the holidays, on the night after we had returned from a weeklong trip. My husband caught Penny eating a nickel she had found on the floor and pulled it from her mouth before she could swallow it. She then had a big bowl of food before going to bed. The next morning, she was lethargic but still walking around. We assumed that she was in a funk because the family she had stayed with had another dog in the house and she probably missed her; she has acted like this before. She then threw up about a dollar in change and, based on our past experiences, we assumed she'd begin feeling better.
The next morning, she had not improved and was not drinking water or eating. I lost it when she went outside to go to the bathroom and her urine was the color of blood. We scooped her up and rushed her to animal urgent care. The vet we saw (Dr. Shenandoah Diehl, the bright spot in this whole experience) told us that it was the pennies that she had eaten that had made her sick.
Penny's stomach acid had partially digested the coins and – because pennies minted in or after 1982 are more than 95% zinc with a thin copper coating – her stomach ate through the copper allowing the to zinc leach out at toxic levels. Because the coins had stayed in her body for more than 12 hours and she had not thrown them up quickly (like she had before), she had acute zinc poisoning.
Symptoms of Zinc Toxicity
Zinc toxicity can manifest as "acute zinc toxicity" or "chronic zinc toxicity." Acute zinc toxicity is caused by the sudden exposure or ingestion of a toxic amount of zinc or zinc containing materials. Chronic zinc toxicity is caused by excessive exposure to zinc over time and can be caused by regular over-consumption of zinc vitamins/lozenges, or chronic exposure to zinc fumes/particles (welders can be afflicted).
Symptoms of Acute Zinc Toxicity
- Stomach pain, headaches, lethargy
- Diarrhea, Vomiting, Nausea
- Urine retention
- Jaundice (yellowing of the skin and whites of the eyes)
- Pale gums and/or tongue
- Orange Colored Feces
- Dark, brown, or red colored urine
Symptoms of chronic zinc toxicity may also include fever, joint pain, chronic cough, low blood pressure, seizures, or metallic taste in the mouth. Some welders or those that spend a lot of time in a similar industrial setting my experience "Zinc Shakes" which is caused by chronic inhalation of zinc particles/fumes.
Without taking your dog or cat to the vet, the only way you can know for certain they have zinc toxicosis is if you catch them in the act. Be aware of your pet's habits and the signs of zinc toxicity as it might save their life.
Coin Ingestion in Children
Small children, toddlers, and babies are at particular risk for penny poisoning and zinc toxicity. Coins are the most commonly ingested foreign object among young children aged 6 months to 3 years. If you suspect your child has eaten coins and observe flu-like symptoms, or if you child is experiencing stomach pain, take them to the hospital for immediate care.
Common Items Made of Zinc
- Pennies (US pennies minted 1982-present, Canadian pennies minted 1997-2001)
- Other coins (certain UK £1, £2 coins)
- Nuts, bolts, nails, and staples
- Jewelry, zippers
- Other galvanized metals (steel coated in zinc oxide)
- Items made of brass (an alloy of zinc and copper)
- Cold lozenges, zinc vitamin supplements
- Board game pieces (ex: old Monopoly pieces)
- Die cast toys (ex: Matchbox and Hot Wheels cars)
- Electrical fuses, certain batteries and car parts
- Certain ointments, creams, lotions, suppositories, and shampoos (some denture creams, diaper rash creams, sunscreens, calamine lotion)
- Certain paints, fertilizers, fungicides, antiseptics
Treatment of Zinc Toxicity in Dogs
If you suspect your dog or cat (or child!) has consumed a penny or similar zinc containing item, get them to the hospital ASAP. The sooner they receive treatment – and the quicker the zinc is removed from their system – the better the prognosis.
If zinc remains in the body for long enough, it can cause hemolysis (or breaking down of red blood cells) which can result in anemia. This stage manifests as blood in urine (which can look brown to red), yellowing of the eyes, and/or pale gums. Later stages of zinc toxicity may result in seizure and marked depression. If left untreated, zinc toxicity can be fatal as a result of multiple organ failure.
In general, for diagnosis, you can expect the following:
- An overall physical examination including questions about your dog's history of foreign object ingestion or past incidence of vomiting up coins or similar items. Younger animals tend to express this behavior more than older ones.
- Your pet may require an x-ray to confirm the presence of a metallic object.
- A vet may perform a blood test, urinalysis, and/or liver and kidney panels.
Treatment of Zinc Toxicity will depend on the extent of the condition:
- If the coins or zinc containing object are still present in the stomach, your vet may induce vomiting.
- Coins that have been in the stomach for a longer period of time may adhere to the stomach lining and require either an endoscopic procedure or surgery to remove it.
- To help flush the zinc out of the system, your vet may hook your dog up to an IV.
- To combat anemia, your pet may be placed in an oxygen chamber or – in extreme cases – be given a blood transfusion.
- During their stay at the hospital, your pet's blood and urine may be monitored.
- Your dog may be on medication during their stay and once you take them home.
Every animal is different, but in general, once the zinc object is removed acute symptoms will resolve within 2-3 days. Fatality will continue to be a possibility as long as blood or urine levels remain abnormal.
Overall, Penny was in the hospital for about 48 hours. She had already thrown up the coins, so the treatment she received was to take care of the zinc that remained in her blood and fluids. She was placed on an IV while her blood was monitored, and when she became anemic, she was placed in an oxygen chamber (which basically looks like an incubator for newborns). Eventually, she needed a blood transfusion. Heck, I've never even had a blood transfusion. It was all quite scary.
When your pet is very sick, the only thing you want to know is if they will be okay; the uncertainty was one of the most difficult things to deal with. We were told not to assume Penny was "out of the woods" until her blood levels returned to a normal. Luckily, we ended up bringing her home on New Years Eve.
Penny took about a week or two to return to her normal appetite and energy level. For the first few days, she would eat nothing but rotisserie chicken (she was hand fed, like the spoiled animal she is). We then worked in plain boiled chicken, rice and potato. She was eating her normal food (more voraciously than before, I might add) after a week.
We realize that we were very lucky. We had always taken care to keep coins and other metal objects out of her reach, but we never knew how important it was to be vigilant at all times. We limit her access to certain rooms in the house and we tell all visitors about her metal fetish so they know to pick up dropped coins immediately. In hopes of curbing her habit, we now stop her from licking any kind of metal object. We know that we may not be able to prevent another incident like this from occurring, but at least we know what to do should it happen again.
Penny's Story on Youtube
Sources and Additional Information
- What is Poisonous to Dogs? What you don't know could kill your pup!
I also wrote a guide to common household items, plants and foods that are poisonous, toxic or deadly in dogs. I realize there are many similar guides out there, so I wrote this with an emphasis on items that are often considered harmless.
- Zinc Toxicosis in Dogs and Cats
- The Merck Vet Manual
This article is was originally written for Hubpages and published on 1/31/13.
All images and text in this article are Copyright ShayMarie on Hubpages. Please do not reproduce any portion of text or copy images without the Copyright holder's written permission.
This article is accurate and true to the best of the author’s knowledge. It is not meant to substitute for diagnosis, prognosis, treatment, prescription, or formal and individualized advice from a veterinary medical professional. Animals exhibiting signs and symptoms of distress should be seen by a veterinarian immediately.