Zinc is toxic to dogs if ingested. I learned this when I was trying to find a sunblock for Murray's nose (he has discoid lupus and the sun causes the tissue to break down on his nose). I had to do a lot of research to come up with a product, developed by a vet, that didn't contain zinc. See article below:
Zinc Toxicity in Dogs and Cats
Toxin
Zinc
Source
Pennies made since 1982, zinc oxide skin preparations such as Desitin, and galvanized metal such as nails and staples. Other sources include calamine lotion, suppositories, shampoos, zinc undecylenate (Desenex), sunblock containing zinc oxide, fertilizers, and paint.
General Information
