My Dog Is Vomiting Blood: Causes and What to Do Right Now

Seeing blood in your dog's vomit is alarming — and it should be taken seriously. Whether it appears as bright red streaks or dark, coffee-ground-like material, blood in a dog's vomit is never something to dismiss or wait out. While some causes are less urgent than others, only a veterinarian can determine what's going on, and many cases require prompt care.

What Does Blood in Dog Vomit Look Like?

There are two appearances you might notice. Bright red blood indicates fresh bleeding in the upper gastrointestinal tract — the esophagus or stomach. Dark, coffee-ground-like material suggests partially digested blood, meaning the bleeding likely occurred higher in the digestive tract and has had time to be processed by stomach acids. Both warrant veterinary attention.

Common Causes of a Dog Vomiting Blood

Gastrointestinal Irritation or Ulcers

One of the most common reasons dogs vomit blood is significant irritation to the stomach lining. This can happen from eating something harsh, stress, or prolonged use of NSAIDs (like ibuprofen or aspirin, which are toxic to dogs). Gastric ulcers can form when the stomach lining erodes, leading to bleeding.

Ingestion of a Foreign Object

Dogs are notorious for swallowing things they shouldn't — bones, toys, sharp sticks, or rocks. These objects can scratch or tear the esophagus or stomach lining, causing bleeding. In more serious cases, a foreign object can cause a blockage that requires emergency surgery.

Hemorrhagic Gastroenteritis (HGE)

HGE is a condition that causes sudden, severe vomiting and bloody diarrhea. It can progress rapidly and lead to dangerous dehydration. The exact cause is not always known, but it's considered a medical emergency.

Toxin or Poison Ingestion

Certain toxins — including rat poison, toxic plants, and some medications — can interfere with blood clotting and cause internal bleeding that manifests as blood in the vomit. If you suspect your dog has ingested something toxic, call the ASPCA Animal Poison Control Center at (888) 426-4435 immediately.

Parvovirus

In unvaccinated or partially vaccinated dogs — especially puppies — parvovirus causes severe vomiting, bloody diarrhea, and rapid deterioration. This is a life-threatening emergency.

Parasites

Intestinal parasites like hookworms or giardia can irritate the gut lining significantly enough to cause bleeding, particularly in young dogs or those with weakened immune systems.

When to Worry: Emergency Signs

Get to a veterinary emergency clinic immediately if your dog shows any of these signs alongside vomiting blood:

• Pale or white gums — indicates possible shock or significant blood loss
• Weakness, collapse, or inability to stand
• Distended or hard abdomen
• Black, tarry stools (digested blood passing through the GI tract)
• Repeated vomiting with no improvement
• Suspected toxin ingestion

Even without these signs, any dog that vomits blood should be seen by a vet the same day — not tomorrow.

What To Do at Home While You Prepare to Go to the Vet

1. Don't panic, but act quickly. Stay calm so you can help your dog.
2. Withhold food and water temporarily to avoid further stomach irritation while you prepare to leave.
3. Take a photo of the vomit if you can — this helps your vet assess the type and amount of blood.
4. Note any potential exposures — did your dog get into anything unusual? What did they eat in the last 24 hours?
5. Call your vet or an emergency clinic before arriving so they can prepare.
6. Don't give your dog any medications — including antacids or human pain relievers — without veterinary guidance.

How Voyage Can Help

Not sure if what you're seeing warrants an emergency room visit? Voyage AI Vet can help you assess your dog's symptoms in real time, around the clock — whether it's 3 AM or a Sunday morning when your regular vet is closed. Describe what you're seeing and get an instant assessment on whether to go to the emergency vet now or schedule a same-day appointment. Starting at $4.99/month.

Want to check if your dog's vomiting is serious? → Describe your dog's symptoms to Voyage

This article is for informational purposes only and is not a substitute for professional veterinary advice. If your dog is vomiting blood, please contact a veterinarian or emergency animal hospital right away.