#29: Vomiting Blood
Blood in a dog’s vomit should always be taken seriously. The blood may appear bright red or look dark and partially digested, similar to coffee grounds. Vomiting blood can happen with poisoning, stomach ulcers, internal bleeding, severe illness, or injuries affecting the digestive system.

Contact a veterinarian immediately if your dog vomits blood, even once. Keep the dog calm and avoid food, treats, or medication unless instructed otherwise. Watch for weakness, pale gums, collapse, or breathing trouble while traveling to the clinic. Quick medical care is important because internal bleeding can become life-threatening.
