Last reviewed: 2026-09-05 · Reference ranges: ASPCA, Pet Poison Helpline & Merck Veterinary Manual
Yes, a protein bar can easily cause diarrhea in dogs. These bars often contain artificial sweeteners like xylitol, which is highly toxic, or other ingredients that upset a dog's stomach. Diarrhea could be the first sign of something more serious. Call the ASPCA Animal Poison Control Center at (888) 426-4435 immediately for guidance.
Do not feed · Dogs · full breakdown on the linked food page
Very often sweetened with xylitol or coated in chocolate. Treat every bar as toxic until you read the label.
The full verdict, portion guidance and serving notes are collected on the Protein & energy bars food facts page.