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Hematemesis (Bloody Vomitus) in Dogs

Author: Dr. med. vet. Gisa Löwe | Last modified: 06.11.2025

Are you unsure what is wrong with your pet? Feel free to use our symptom checker for more clarity.

HematemesisHematemesis is the Vomiting of blood, indicating Bleeding in the upper gastrointestinal tract. In dogs and cats, this can be caused by ulcers, foreign bodies, poisoning, or Tumors and requires immediate veterinary attention. (bloody vomitus) in dogs, also known as hematemesisHematemesis is the Vomiting of blood, indicating Bleeding in the upper gastrointestinal tract. In dogs and cats, this can be caused by ulcers, foreign bodies, poisoning, or Tumors and requires immediate veterinary attention., is the presence of blood in a dog’s vomit. This can appear as fresh, red blood or as digested blood that looks like coffee grounds.

Can Occur with the Following Diseases:

Basics and possible causes

Vomiting in dogs is a common symptom that can occur for a variety of reasons. If the vomit contains blood, it requires special attention as it may indicate more serious health problems. The causes can range from relatively harmless to potentially life-threatening conditions.

One of the most common causes of hematemesisHematemesis is the Vomiting of blood, indicating Bleeding in the upper gastrointestinal tract. In dogs and cats, this can be caused by ulcers, foreign bodies, poisoning, or Tumors and requires immediate veterinary attention. (bloody vomitus) is irritation or injury to the gastric mucosaMucosa, also called mucous membrane, refers to the moist lining of body cavities that are connected to the outside world, such as the mouth, nose, lungs, and gastrointestinal tract. It serves to protect and facilitate the absorption of nutrients., often due to swallowing sharp objects such as bones or toy parts. This mechanical damage can lead to bleeding. Similarly, ingesting toxicToxic means "poisonous" and refers to substances that can have harmful effects on the body, including damage to organs, cells, or disruption of metabolic processes. substances such as certain plants, chemicals, or medications can lead to gastrointestinalGastrointestinal refers to the gastrointestinal tract, a system that extends from the oral cavity to the anus and is responsible for the digestion of food and the absorption of nutrients. bleeding.

Infections, especially from viruses such as parvovirus, can also cause hematemesisHematemesis is the Vomiting of blood, indicating Bleeding in the upper gastrointestinal tract. In dogs and cats, this can be caused by ulcers, foreign bodies, poisoning, or Tumors and requires immediate veterinary attention. (bloody vomitus). These infections often affect puppies or unvaccinated dogs and manifest quickly and severely. ParasiticParasitic refers to diseases or conditions caused by parasites. Parasitic infections can affect the digestive tract, skin, and other organ systems. infections, such as hookworms, can also damage the mucous membrane and cause bleeding.

Diseases of the internal organs, especially the liver and kidneys, can also cause hematemesisHematemesis is the Vomiting of blood, indicating Bleeding in the upper gastrointestinal tract. In dogs and cats, this can be caused by ulcers, foreign bodies, poisoning, or Tumors and requires immediate veterinary attention. (bloody vomitus). These organs play an essential role in detoxification and maintaining homeostasisHomeostasis is an organism's ability to maintain the internal balance of its bodily environment by regulating physiological processes. This includes controlling temperature, pH value, blood sugar levels, and other vital parameters. in the body. If they do not function properly, this can lead to changes in blood clotting and, consequently, to bleeding.

Severe systemic diseases such as cancerCancer refers to the uncontrolled proliferation of cells that can lead to tumors or spread throughout the body. Various types of cancer occur in dogs and cats, ranging from skin cancer to lymphomas., especially gastric or intestinalIntestinal refers to the intestine, the part of the digestive tract that extends from the stomach to the anus. Intestinal diseases affect the small and/or large intestine. tumors, can also lead to hematemesisHematemesis is the Vomiting of blood, indicating Bleeding in the upper gastrointestinal tract. In dogs and cats, this can be caused by ulcers, foreign bodies, poisoning, or Tumors and requires immediate veterinary attention. (bloody vomitus). These Tumors can destroy the mucous membrane and cause bleeding. Similarly, a stomach ulcerAn ulcer is an open wound or erosion of the skin or mucous membrane that often heals poorly and can be caused by a variety of factors, including infections and chronic inflammatory conditions. caused by stressStress refers to the state of an organism reacting to external stimuli or demands. In veterinary medicine, stress can have physical or psychological effects on animals, impacting their health and well-being., medication, or bacterial infections can lead to bleeding.

Typical accompanying symptoms

Loss of appetite: A dog suffering from hematemesisHematemesis is the Vomiting of blood, indicating Bleeding in the upper gastrointestinal tract. In dogs and cats, this can be caused by ulcers, foreign bodies, poisoning, or Tumors and requires immediate veterinary attention. (bloody vomitus) often loses interest in food and water. This can lead to rapid weight loss and dehydrationDehydration occurs when the body loses more fluid than it takes in. This can lead to a number of problems, including headaches, Dizziness, and in extreme cases, renal failure or Cardiovascular collapse..
DiarrheaDiarrhea refers to the condition of frequent, watery bowel movements, which can be a sign of infections, digestive disorders, or other health problems.: HematemesisHematemesis is the Vomiting of blood, indicating Bleeding in the upper gastrointestinal tract. In dogs and cats, this can be caused by ulcers, foreign bodies, poisoning, or Tumors and requires immediate veterinary attention. (bloody vomitus) is often accompanied by diarrheaDiarrhea refers to the condition of frequent, watery bowel movements, which can be a sign of infections, digestive disorders, or other health problems., which may also contain blood. This is an indicationIndication refers to a valid reason or rationale for using a specific treatment, medication, or medical procedure. It is based on the diagnosis and the patient's clinical condition. of a severe gastrointestinalGastrointestinal refers to the gastrointestinal tract, a system that extends from the oral cavity to the anus and is responsible for the digestion of food and the absorption of nutrients. disturbance.
Lethargy: The dog appears tired and has little energy as the body struggles with the loss of blood and fluid.
Pallor of the mucous membranes: The mucous membranes in the mouth, which are normally pink, may appear pale or even whitish, indicating anemia.
AbdominalThe term "abdominal" refers to anything that concerns the belly or the abdomen. It is an adjectival expression used to describe the location, symptoms, or conditions that occur in the abdominal area. pain: The dog may show signs of abdominalThe term "abdominal" refers to anything that concerns the belly or the abdomen. It is an adjectival expression used to describe the location, symptoms, or conditions that occur in the abdominal area. pain, such as whining, restlessness, or adopting a hunched posture.
Weakness: Due to blood loss and dehydrationDehydration occurs when the body loses more fluid than it takes in. This can lead to a number of problems, including headaches, Dizziness, and in extreme cases, renal failure or Cardiovascular collapse., the dog may appear weak and wobbly on its legs.
Fever: An elevated body temperature may indicate an underlying infectionAn infection is the colonization and multiplication of pathogens such as bacteria, viruses, fungi, or parasites in an organism, which often, but not always, leads to a disease. or Inflammatory conditions.

When to visit the vet?

It is crucial to see a veterinarian as soon as hematemesisHematemesis is the Vomiting of blood, indicating Bleeding in the upper gastrointestinal tract. In dogs and cats, this can be caused by ulcers, foreign bodies, poisoning, or Tumors and requires immediate veterinary attention. (bloody vomitus) is detected in a dog. This is especially true if the dog additionally shows any of the above symptoms or the vomiting does not subside within a short period of time.

An immediate veterinary visit is also indicated if the dog shows signs of shock, such as pale mucous membranes, rapid heart rate, or shallow breathing. These symptoms may indicate significant blood loss or a severe systemic disease.

If the dog has pre-existing health problems, such as liver or kidney disease, or if it is taking certain medications, it is particularly important to act quickly in the event of hematemesisHematemesis is the Vomiting of blood, indicating Bleeding in the upper gastrointestinal tract. In dogs and cats, this can be caused by ulcers, foreign bodies, poisoning, or Tumors and requires immediate veterinary attention. (bloody vomitus).

Symptom recognition for animal owners and veterinary diagnostic procedures

It is important for the pet owner to carefully observe the vomit and provide accurate information to the veterinarian. This includes the amount and appearance of the blood, the frequency of vomiting, and any other symptoms observed. This information can help the veterinarian assess the severity of the condition.

The veterinarian will usually perform a thorough clinical examination and make initialInitial means beginning or at the start. In medicine, it can refer to the first symptoms of a disease or the first phase of a treatment process. assumptions based on the symptoms and medical historyThe medical history is the systematic collection of a patient's medical history through questioning. It includes information about previous illnesses, treatments, allergies, and lifestyle habits.. Blood tests are often necessary to detect signs of anemia or infections and to check organ function.

Imaging procedures such as X-rays or ultrasound can be performed to look for foreign bodies, Tumors, or other structural abnormalities in the gastrointestinalGastrointestinal refers to the gastrointestinal tract, a system that extends from the oral cavity to the anus and is responsible for the digestion of food and the absorption of nutrients. tract. In some cases, an endoscopyEndoscopy is a diagnostic procedure that uses an endoscope (a thin, flexible tube with a light source and a camera at the end) to examine and visualize the inside of the body, often for diagnostic or therapeutic purposes. may be necessary to directly examine the lining of the stomach and take tissue samples for a biopsyA biopsy is a medical procedure in which a small amount of tissue is removed from the body to be examined under a microscope for signs of disease. Biopsies can help diagnose cancer and other conditions..

What can pet owners do and professional therapy options

While waiting for the veterinarian, the dog should not have access to food or water to avoid further vomiting. In some cases, however, it may be advisable to offer the dog small amounts of water to prevent dehydrationDehydration occurs when the body loses more fluid than it takes in. This can lead to a number of problems, including headaches, Dizziness, and in extreme cases, renal failure or Cardiovascular collapse. until the veterinarian decides otherwise.

Keep the dog calm and comfortable to minimize stressStress refers to the state of an organism reacting to external stimuli or demands. In veterinary medicine, stress can have physical or psychological effects on animals, impacting their health and well-being., which could worsen the symptoms. The dog should be kept in a warm, quiet room where it will not be disturbed.

It is important not to administer home remedies or human medications unless a veterinarian has specifically recommended it. Some medications can worsen the situation or cause additional complications.

Note all the symptoms you observe and bring this information with you to the vet appointment. This can help speed up the diagnosisA diagnosis is the identification of a disease or condition by its symptoms and/or results from diagnostic tests. It is the first step in the management and treatment of patients. and ensure the best possible treatment.

Outlook on current research

Current research on hematemesisHematemesis is the Vomiting of blood, indicating Bleeding in the upper gastrointestinal tract. In dogs and cats, this can be caused by ulcers, foreign bodies, poisoning, or Tumors and requires immediate veterinary attention. (bloody vomitus) in dogs focuses on identifying underlying mechanisms that lead to this symptom. Researchers are investigating how various diseases of the gastrointestinalGastrointestinal refers to the gastrointestinal tract, a system that extends from the oral cavity to the anus and is responsible for the digestion of food and the absorption of nutrients. tract affect the mucous membrane and can lead to bleeding. A particular focus is on the role of Helicobacter infections, which are known to cause gastric Inflammatory conditions that can lead to hematemesisHematemesis is the Vomiting of blood, indicating Bleeding in the upper gastrointestinal tract. In dogs and cats, this can be caused by ulcers, foreign bodies, poisoning, or Tumors and requires immediate veterinary attention. (bloody vomitus). By deciphering the exact pathogenesisPathogenesis describes the process of the origin and development of a disease, including the mechanisms that lead to the disease's symptoms and signs., scientists hope to develop more targeted treatment strategies.

Another area of research is the genetic predispositionA predisposition is an innate inclination or susceptibility of an organism to certain diseases or conditions. In dogs and cats, there may be a genetic predisposition to certain conditions such as hip dysplasia or certain heart diseases. of dogs to diseases that can cause hematemesisHematemesis is the Vomiting of blood, indicating Bleeding in the upper gastrointestinal tract. In dogs and cats, this can be caused by ulcers, foreign bodies, poisoning, or Tumors and requires immediate veterinary attention. (bloody vomitus). Genetic studies aim to identify specific markers that indicate an increased susceptibility to such diseases. In the long term, these findings could help to identify risk groups and develop preventive measures to minimize the occurrence of hematemesisHematemesis is the Vomiting of blood, indicating Bleeding in the upper gastrointestinal tract. In dogs and cats, this can be caused by ulcers, foreign bodies, poisoning, or Tumors and requires immediate veterinary attention. (bloody vomitus).

In addition, the role of nutrition and environmental factors is being investigated in research. Scientists are analyzing how certain foods or environmental toxins can damage the gastrointestinalGastrointestinal refers to the gastrointestinal tract, a system that extends from the oral cavity to the anus and is responsible for the digestion of food and the absorption of nutrients. mucosaMucosa, also called mucous membrane, refers to the moist lining of body cavities that are connected to the outside world, such as the mouth, nose, lungs, and gastrointestinal tract. It serves to protect and facilitate the absorption of nutrients. and cause bleeding. Experiments with different feed compositions and the observation of environmental changes could provide valuable information on how hematemesisHematemesis is the Vomiting of blood, indicating Bleeding in the upper gastrointestinal tract. In dogs and cats, this can be caused by ulcers, foreign bodies, poisoning, or Tumors and requires immediate veterinary attention. (bloody vomitus) is influenced by external factors.

The development of new diagnostic procedures for the early detection of causes for hematemesisHematemesis is the Vomiting of blood, indicating Bleeding in the upper gastrointestinal tract. In dogs and cats, this can be caused by ulcers, foreign bodies, poisoning, or Tumors and requires immediate veterinary attention. (bloody vomitus) is also an active field of research. Modern imaging techniques, endoscopies, and laboratory tests are constantly being improved to enable more precise and faster diagnoses. These technologies could make it easier for veterinarians to determine the exact cause of hematemesisHematemesis is the Vomiting of blood, indicating Bleeding in the upper gastrointestinal tract. In dogs and cats, this can be caused by ulcers, foreign bodies, poisoning, or Tumors and requires immediate veterinary attention. (bloody vomitus) and initiate appropriate treatments.

Another aspect of the research is the investigation of anti-inflammatory and procoagulant drugs for the treatment of hematemesisHematemesis is the Vomiting of blood, indicating Bleeding in the upper gastrointestinal tract. In dogs and cats, this can be caused by ulcers, foreign bodies, poisoning, or Tumors and requires immediate veterinary attention. (bloody vomitus). Clinical studies are evaluating the efficacy and safety of new drugs that aim to stop bleeding and promote healing of the gastrointestinalGastrointestinal refers to the gastrointestinal tract, a system that extends from the oral cavity to the anus and is responsible for the digestion of food and the absorption of nutrients. mucosaMucosa, also called mucous membrane, refers to the moist lining of body cavities that are connected to the outside world, such as the mouth, nose, lungs, and gastrointestinal tract. It serves to protect and facilitate the absorption of nutrients.. Research in this area could lead to new therapeutic options that improve the prognosisThe prognosis is the prediction of the likely course and outcome of a disease based on the general state of health, the nature of the disease, and the response to treatment. It can provide information on how a disease is expected to develop. for affected dogs.

Frequently asked questions

What causes hematemesisHematemesis is the Vomiting of blood, indicating Bleeding in the upper gastrointestinal tract. In dogs and cats, this can be caused by ulcers, foreign bodies, poisoning, or Tumors and requires immediate veterinary attention. (bloody vomitus) in dogs? HematemesisHematemesis is the Vomiting of blood, indicating Bleeding in the upper gastrointestinal tract. In dogs and cats, this can be caused by ulcers, foreign bodies, poisoning, or Tumors and requires immediate veterinary attention. (bloody vomitus) can be caused by a variety of factors, including gastrointestinalGastrointestinal refers to the gastrointestinal tract, a system that extends from the oral cavity to the anus and is responsible for the digestion of food and the absorption of nutrients. Inflammatory conditions, ulcers, poisoning, foreign bodies in the gastrointestinalGastrointestinal refers to the gastrointestinal tract, a system that extends from the oral cavity to the anus and is responsible for the digestion of food and the absorption of nutrients. tract, or severe infections.
How can I tell if my dog has hematemesisHematemesis is the Vomiting of blood, indicating Bleeding in the upper gastrointestinal tract. In dogs and cats, this can be caused by ulcers, foreign bodies, poisoning, or Tumors and requires immediate veterinary attention. (bloody vomitus)? HematemesisHematemesis is the Vomiting of blood, indicating Bleeding in the upper gastrointestinal tract. In dogs and cats, this can be caused by ulcers, foreign bodies, poisoning, or Tumors and requires immediate veterinary attention. (bloody vomitus) in dogs can manifest as the presence of fresh, red blood or as coffee-colored vomit, which indicates digested blood.
Is hematemesisHematemesis is the Vomiting of blood, indicating Bleeding in the upper gastrointestinal tract. In dogs and cats, this can be caused by ulcers, foreign bodies, poisoning, or Tumors and requires immediate veterinary attention. (bloody vomitus) in dogs an emergency? Yes, hematemesisHematemesis is the Vomiting of blood, indicating Bleeding in the upper gastrointestinal tract. In dogs and cats, this can be caused by ulcers, foreign bodies, poisoning, or Tumors and requires immediate veterinary attention. (bloody vomitus) should be considered an emergency. It is important to see a veterinarian as soon as possible, as it may indicate serious health problems.
Can hematemesisHematemesis is the Vomiting of blood, indicating Bleeding in the upper gastrointestinal tract. In dogs and cats, this can be caused by ulcers, foreign bodies, poisoning, or Tumors and requires immediate veterinary attention. (bloody vomitus) in dogs stop on its own? In some cases, the vomiting may stop temporarily, but without treatment, the underlying cause may persist and lead to further blood loss or other complications.
What treatment options are available for hematemesisHematemesis is the Vomiting of blood, indicating Bleeding in the upper gastrointestinal tract. In dogs and cats, this can be caused by ulcers, foreign bodies, poisoning, or Tumors and requires immediate veterinary attention. (bloody vomitus) in dogs? Treatment depends on the underlying cause and may include medications to reduce Inflammatory conditions, dietary adjustments, surgical procedures, or the removal of foreign bodies.
Can certain foods cause hematemesisHematemesis is the Vomiting of blood, indicating Bleeding in the upper gastrointestinal tract. In dogs and cats, this can be caused by ulcers, foreign bodies, poisoning, or Tumors and requires immediate veterinary attention. (bloody vomitus) in dogs? Yes, spicy, heavy, or toxicToxic means "poisonous" and refers to substances that can have harmful effects on the body, including damage to organs, cells, or disruption of metabolic processes. foods can irritate the gastrointestinalGastrointestinal refers to the gastrointestinal tract, a system that extends from the oral cavity to the anus and is responsible for the digestion of food and the absorption of nutrients. mucosaMucosa, also called mucous membrane, refers to the moist lining of body cavities that are connected to the outside world, such as the mouth, nose, lungs, and gastrointestinal tract. It serves to protect and facilitate the absorption of nutrients. and cause hematemesisHematemesis is the Vomiting of blood, indicating Bleeding in the upper gastrointestinal tract. In dogs and cats, this can be caused by ulcers, foreign bodies, poisoning, or Tumors and requires immediate veterinary attention. (bloody vomitus). A balanced and appropriate diet is important to avoid such problems.
How can I prevent my dog from getting hematemesisHematemesis is the Vomiting of blood, indicating Bleeding in the upper gastrointestinal tract. In dogs and cats, this can be caused by ulcers, foreign bodies, poisoning, or Tumors and requires immediate veterinary attention. (bloody vomitus)? Regular veterinary check-ups, a balanced diet, avoiding toxicToxic means "poisonous" and refers to substances that can have harmful effects on the body, including damage to organs, cells, or disruption of metabolic processes. substances, and a safe environment can help reduce the risk of gastrointestinalGastrointestinal refers to the gastrointestinal tract, a system that extends from the oral cavity to the anus and is responsible for the digestion of food and the absorption of nutrients. problems.
Which breeds are particularly susceptible to hematemesisHematemesis is the Vomiting of blood, indicating Bleeding in the upper gastrointestinal tract. In dogs and cats, this can be caused by ulcers, foreign bodies, poisoning, or Tumors and requires immediate veterinary attention. (bloody vomitus)? Certain breeds, such as Boxers, Great Danes, and Labrador Retrievers, may be genetically more susceptible to gastrointestinalGastrointestinal refers to the gastrointestinal tract, a system that extends from the oral cavity to the anus and is responsible for the digestion of food and the absorption of nutrients. diseases that lead to hematemesisHematemesis is the Vomiting of blood, indicating Bleeding in the upper gastrointestinal tract. In dogs and cats, this can be caused by ulcers, foreign bodies, poisoning, or Tumors and requires immediate veterinary attention. (bloody vomitus).
Can stressStress refers to the state of an organism reacting to external stimuli or demands. In veterinary medicine, stress can have physical or psychological effects on animals, impacting their health and well-being. triggerA trigger is a stimulus that elicits a specific reaction or state. In veterinary medicine, this can refer to emotional responses, such as fear or aggression, or medical conditions, such as seizures in dogs and cats. hematemesisHematemesis is the Vomiting of blood, indicating Bleeding in the upper gastrointestinal tract. In dogs and cats, this can be caused by ulcers, foreign bodies, poisoning, or Tumors and requires immediate veterinary attention. (bloody vomitus) in dogs? Yes, stressStress refers to the state of an organism reacting to external stimuli or demands. In veterinary medicine, stress can have physical or psychological effects on animals, impacting their health and well-being. can lead to a variety of health problems in dogs, including Magen-Darm-Störungen that can cause hematemesisHematemesis is the Vomiting of blood, indicating Bleeding in the upper gastrointestinal tract. In dogs and cats, this can be caused by ulcers, foreign bodies, poisoning, or Tumors and requires immediate veterinary attention. (bloody vomitus).
What should I do if my dog shows hematemesisHematemesis is the Vomiting of blood, indicating Bleeding in the upper gastrointestinal tract. In dogs and cats, this can be caused by ulcers, foreign bodies, poisoning, or Tumors and requires immediate veterinary attention. (bloody vomitus)? Seek veterinary attention immediately. It is important to quickly determine the cause of the symptom and initiate appropriate treatment to prevent further complications.