The combination of vomiting and dark bloody stools known as melena, is a serious medical sign in dogs. It can indicate a number of underlying medical conditions, some of which are life-threatening.
Below are explanations of some possible causes of vomiting and dark bloody stools in dogs:
Gastrointestinal Bleeding
Gastrointestinal (GI) bleeding occurs when there is damage to the lining of the stomach or intestines, causing blood to be released into the digestive tract. This can lead to vomiting of blood or dark, coffee-ground-like material, as well as dark, bloody stools. Common causes of gastrointestinal bleeding in dogs include:
- Ulcers
- Gastritis (inflammation of the stomach)
- Intestinal inflammation (such as colitis or enteritis)
- Cancer of the stomach or intestines
- Foreign object ingestion
- Certain medications (such as aspirin or ibuprofen)
Parvovirus
Parvovirus is a highly contagious viral infection that affects dogs, particularly puppies. It can cause severe vomiting and diarrhea, leading to dehydration and loss of electrolytes. The diarrhea is often bloody and may have a foul odor.
Hemorrhagic Gastroenteritis (HGE)
HGE is a sudden, severe inflammation of the stomach and intestines that can cause vomiting and bloody diarrhea. The exact cause of HGE is unknown, but it is thought to be related to an immune system overreaction to certain triggers, such as stress, dietary indiscretion, or certain infections.
Liver Disease
Liver disease can lead to vomiting, diarrhea, and dark, bloody stools. The liver is responsible for filtering toxins from the blood, and when it is damaged, these toxins can build up and cause a variety of health problems.
Pancreatitis
Pancreatitis is an inflammation of the pancreas, a gland that helps digest food and regulates blood sugar levels. Pancreatitis can cause vomiting, abdominal pain, and bloody diarrhea.
Addison's Disease
Addison's disease is a condition that occurs when the adrenal glands, which produce hormones that help regulate the body's response to stress, are damaged or destroyed. Addison's disease can cause a variety of symptoms, including vomiting, diarrhea, weight loss, and dark, bloody stools.
Coagulopathies
Coagulopathies are disorders that affect the blood's ability to clot properly. This can lead to uncontrollable bleeding, which can manifest as vomiting of blood and dark, bloody stools. Common causes of coagulopathies in dogs include:
- Vitamin K deficiency
- Liver disease
- Certain medications (such as warfarin or aspirin)
- Autoimmune disorders
- Cancer
If your dog is experiencing vomiting and dark bloody stools, it is important to seek veterinary attention immediately. The veterinarian will be able to determine the cause of the symptoms and provide appropriate treatment.