Store-bought fake blood products used in Halloween costumes are unlikely to pose a pet safety issue, because they are nontoxic, Dr. Flint says, but she cautions pet parents to always check package ingredients. The best precaution is to keep potentially tempting products away from curious noses and mouths.
Homemade fake blood can be quite appealing to pets because it often includes ingredients like powdered sugar, corn syrup, corn starch and food coloring. And some recipes contain a small amount of chocolate (usually cocoa powder or chocolate syrup), she notes.
“A lick or small taste would still be okay, but if a small dog ate an entire batch of homemade fake blood with cocoa powder in it, that might cause symptoms such as vomiting, diarrhea, excitability and maybe elevated heart rate, depending on how much was ingested in comparison to the size of the dog,” she warns.
Dr. Flint also says that pets can be drawn to eating or chewing odd things, so plastic caps and packaging material could be a concern. Materials like these are not digestible and can become lodged in the gastrointestinal tract.