How does zinc destroy red blood cells?
Zinc is a heavy metal. Once absorbed, high levels damage red blood cells (haemolytic anaemia) and can injure the liver and kidneys. Coins stay in the stomach and keep releasing zinc, so symptoms can build over 1–3 days.
About the dose levels
Single coins rarely cause poisoning in large dogs, but one penny can be toxic to a small dog. Zinc poisoning in dogs is reported above roughly 1–2 g of zinc total. The calculator shows mg per kg.
Single coins rarely cause poisoning in large dogs, but one penny can be toxic to a small dog. Zinc poisoning in dogs is reported above roughly 1–2 g of zinc total. The calculator shows mg per kg.
Symptoms of zinc poisoning
- Vomiting, diarrhoea, not eating (may start days later)
- Pale or yellow gums (anaemia)
- Lethargy, weakness, dark urine
- Rapid heart rate, fast breathing
- Liver/kidney signs in severe cases
What to do right now
- Call your vet if your dog ate any coins or zinc pills — even one penny in a small dog.
- X-rays can show coins; the vet may remove them before they release too much zinc.
- Bring the zinc pill bottle if supplements were eaten.
- Treatment may need a blood transfusion in severe anaemia.
If your pet is already showing symptoms, don’t wait for a calculator result — call your vet or the ASPCA Poison Control center (888) 426-4435 immediately.
Sources & further reading
- ASPCA Animal Poison Control — pet poison database & dosage references
- Pet Poison Helpline — toxicology triage guidelines
- Merck Veterinary Manual — toxicology monographs
- Vets Now (UK) — emergency toxicosis guidance