When a dog begins vomiting blood and mucus, it is one of the most distressing symptoms for pet owners to witness. This combination often points to a serious underlying condition that requires close attention.
We outline the common reasons for a dog vomiting blood and mucus, what you can do at home, and when to seek veterinary help.
Dog Vomiting Blood and Mucus — Why It Happens
Vomiting blood and mucus in dogs usually signals irritation, injury, or disease in the gastrointestinal tract. It can be caused by stomach ulcers, infections, ingestion of foreign objects, poisoning, or even severe inflammation such as gastritis. In some cases, systemic illnesses like liver or kidney disease can also be responsible.
Because blood in vomit can indicate active bleeding, it is not a symptom to ignore and should be taken seriously.
Dog Vomiting Blood and Mucus: Common Causes
Gastritis
Gastritis, or inflammation of the stomach lining, is a frequent cause of vomiting blood mixed with mucus. This condition may develop from dietary indiscretion, infections, or exposure to toxins.
A dog with gastritis often vomits repeatedly, sometimes producing frothy mucus streaked with red or brown blood.
Because prolonged vomiting can quickly dehydrate a dog, this condition should be addressed promptly.
Read more: Dog Vomiting Blood and Mucus but Acting Normal (Here’s why)
Stomach or Intestinal Ulcers
Ulcers in the stomach or intestines can cause significant bleeding, leading to the presence of blood in vomit.
Mucus often appears alongside blood because ulcers irritate the lining of the digestive tract.
Dogs with ulcers may also show signs of loss of appetite, abdominal pain, and weakness. Left untreated, ulcers can worsen and lead to life-threatening internal bleeding.
Ingested Toxins or Foreign Objects
When a dog consumes something toxic, such as rat poison or household chemicals, it can lead to internal bleeding and irritation.
Foreign objects, like bones, toys, or cloth, may scrape or lodge in the stomach and intestines, causing injury and bleeding.
Vomiting blood and mucus in these cases is a red flag that the stomach lining or intestines are being damaged.
Severe Gastrointestinal Infections
Bacterial, viral, or parasitic infections of the digestive tract can also result in vomiting blood and mucus.
Parvovirus, in particular, is notorious for causing bloody, mucus-filled vomit and diarrhea, especially in puppies.
Dogs with infections are usually very ill, showing lethargy, fever, and refusal to eat or drink. Quick veterinary intervention is essential to manage these cases.
Liver or Kidney Disease
Systemic illnesses like liver disease or kidney failure can disrupt the normal clotting ability of blood and irritate the digestive tract.
As a result, dogs may vomit blood along with mucus. These dogs often have additional symptoms such as weight loss, increased thirst, pale gums, and bad breath.
Because these diseases are chronic and progressive, early diagnosis is critical.
Tumors or Cancer
Unfortunately, tumors in the stomach or intestines can also lead to bloody and mucus-filled vomit.
These growths may bleed on their own or cause blockages that irritate the digestive tract.
Dogs with cancer may also experience gradual weight loss, weakness, and changes in appetite. While cancer is more common in older dogs, it can appear in younger pets as well.
What to Do If Your Dog Is Vomiting Blood and Mucus
If your dog vomits blood and mucus once but seems otherwise normal, you can temporarily withhold food for 12 hours to allow the stomach to rest, while ensuring fresh water is available.
Offer small amounts of bland food such as boiled chicken and rice once vomiting subsides. Monitor closely for signs of improvement or worsening.
Do not give over-the-counter medications without veterinary approval, as some can worsen bleeding.
Keep your dog calm and prevent them from eating grass, garbage, or unknown objects during recovery. If vomiting continues, increases in frequency, or your dog seems weak or unwell, professional care is essential.
When to Call or Visit Your Vet
Immediate veterinary attention is necessary if vomiting blood and mucus is accompanied by lethargy, collapse, pale gums, or abdominal swelling.
These may indicate severe blood loss or an obstruction. Puppies and senior dogs are at higher risk of rapid deterioration and should be evaluated right away.
Even if your dog vomits only once but produces a significant amount of blood, a veterinary exam is recommended.
A vet can perform tests such as blood work, x-rays, or ultrasounds to determine the underlying cause and provide supportive care, including fluids, anti-nausea medications, and hospitalization if needed.
Read more: Dog Vomiting Bile and Mucus (What it means)
Key Takeaway
Vomiting blood and mucus in dogs is always a concerning sign that should not be dismissed. While some causes may be mild, others are life-threatening and require immediate veterinary care.
Dog owners should monitor their dog’s condition closely, provide supportive care at home when appropriate, and seek professional help as soon as warning signs appear. Acting quickly gives your dog the best chance of recovery and peace of mind for you.