The color of a cat’s poop can provide important information to caregivers and veterinarians. Normal cat poop should be a similar color to milk chocolate and soft to firm in texture. Most cats will pass poop once or twice a day.
Black cat poop is commonly associated with gastrointestinal bleeding, which has a number of pathologies from mild to life-threatening.
Blood in cat poop may be black and tarry or bright red. The color of blood in cat poop relates to the location of the bleeding:
- Bright red blood in cat poop (hematochezia) originates from the lower gastrointestinal tract.
- Black cat poop (melena) relates to bleeding in the upper gastrointestinal tract.
Steps to take at home if your cat’s poop is black
Black cat poop (melena) often requires veterinary treatment. At home, there are a few things that you can try to help your cat, such as:
- Feeding them a bland diet. Things like plain chicken are very easy for your cat’s stomach to digest and can help with any GI issues that may be causing the black stool
- Give them a probiotic. Many times black stool is caused by a GI issue. This can cause a disturbance in the bacteria commonly found in your cat’s stomach and intestines. Giving your cat a probiotic can help rebalance the bacteria load in their stomach.
In any case, you should see your local vet. Many times cats whose poop is black will need to see a vet as this usually indicates that there is something more serious going on in their intestines than just a simple GI issue. You should not delay veterinary treatment. See the next section listing the top causes of black stools, and how to prepare for your vet’s visit.
What causes black poop in cats?
The medical term for black, tarry feces is melena and occurs when there is bleeding in the mouth, esophagus, stomach, and duodenum (upper GI tract). As blood passes through the gastrointestinal (GI) tract, enzymes break down the hemoglobin in the blood, causing the characteristic dark, tarry stools which are often accompanied by a strong odor. Top causes of black cat poop include:
- Esophageal or gastric ulcers
- Ingested foreign body, such as a cooked chicken bone
- Blood clotting disorders (hemophilia, thrombocytopenia, Von Willebrand’s disease (vWD), disseminated intravascular coagulation, Chédiak-Higashi syndrome, myelodysplasia)
- Esophageal or gastric tumors
- Kidney or liver failure
- Gastrointestinal inflammation (esophagitis, gastritis, colitis)
- Inflammatory bowel disease
- Ingestion of blood from the mouth
- Post-surgery bleeding
- Hookworm infection – read our article about worms in cat poop.
- Poisoning (NSAIDs, raisins, grapes, heavy metals, vitamin D)
- Ingestion of licorice, blueberries, and beetroot can cause stool color changes but is unlikely in cats, however, administration of activated charcoal can cause black stools
Clinical signs/symptoms of cats with black poop
The most prominent symptom is the presence of dark, tarry stools. Additional symptoms will depend on the underlying cause of dark tarry stools as well as the amount of blood that has been lost. Typical symptoms to watch for include:
- Foul smelling poops
- Anemia due to blood loss
- Lethargy
- Pale mucus membranes
- Loss of appetite
- Weight loss
- Jaundice (yellow gums)
- Polyuria/polydipsia (increased urination and thirst)
- Abdominal pain
- Hematuria (blood in the urine)
Treatment
Black cat poop (melena) often cannot be treated at home and requires veterinary treatment to find the underlying cause and tailor a treatment plan depending on the prognosis:
- Antiparasitic medications can be prescribed for cats with hookworm infection
- Ranitidine, cimetidine, or famotidine are H2 blockers used to treat gastric ulcers in cats. They work by reducing stomach acid secretion and protecting the mucosal lining. Omeprazole is a proton pump inhibitor (PPI) that also inhibits stomach acid secretion.
- Foreign bodies may be removed via endoscopy or surgical intervention (laparotomy, enterotomy, or gastrostomy). Surgical treatment to remove a foreign body involves making an incision in the abdominal cavity close to the location of the foreign body and manually removing it, along with repairing damaged tissue and excision of any necrotic tissue.
- Finding the cause of blood clotting disorders is important for the veterinarian to determine an effective treatment. In some cases, medical management of the disorder will be implemented as a cure is not always possible. Avoid surgery unless absolutely necessary. Blood or plasma transfusions can keep red blood cells and platelets within normal parameters.
- Benign esophageal or gastric tumors can be removed surgically, however, by the time malignant tumors have been diagnosed, they have already metastasized. Radiation therapy may be used to decrease the size of the tumor, but is generally not curative.
- Inflammatory bowel disease may be managed with a highly digestible, low-fat diet containing a novel protein diet, corticosteroids for their anti-inflammatory and immune-suppressing properties, and azathioprine (Imuran), an immunosuppressive drug.
- Dietary modifications, corticosteroids, or other drugs to suppress the immune system, and in some cases, antibiotics.
- Post-surgical bleeding may be normal in some cases, however, if it is prolonged, may require surgical repair.
- Poisoning may be treated by inducing vomiting or pumping the stomach, followed by administration of activated charcoal, endoscopy, or surgery to remove heavy metals such as lead and supportive care while the cat recovers.
- Supportive care may include fluids to treat and prevent dehydration and electrolyte derangements, as well as a bland diet to rest the gastrointestinal tract and antiemetics for cats with nausea and vomiting.
Diagnosis
Veterinary attention is important if your cat is passing dark, tarry stools. The veterinarian will perform a complete physical examination and obtain a medical history from you, which will include any medications or supplements the cat is on, how long have symptoms been present, is the cat eating and drinking as normal, and whether have you noticed any additional symptoms.
Diagnostic workup:
Diagnostic tests will be necessary for the veterinarian to diagnose the underlying cause of black tarry poops.
- Biochemical profile: A test on the clear/fluid portion of the blood, the biochemical profile measures a number of chemicals and enzymes which provides important information on the status of organs and electrolytes.
- Complete blood count: A blood test that measures the cellular components of the blood (red blood cells, white blood cells, and platelets.
- Coagulation profiles: If abnormalities are detected in the complete blood count, the veterinarian will run a series of tests to measure the body’s ability to form a blood clot. Typical tests include aPTT, INR, fibrinogen, and platelets.
- Urinalysis: A urine sample is evaluated for its physical properties, which include specific gravity, color, and clarity, and biochemically for pH, protein, glucose, bilirubin, and ketones, and microscopically for blood cells, crystals, casts (solid, tubular deposits) and bacteria which can detect diseases such as diabetes, kidney disease and infections of the urinary tract.
- Gastroscopy: A medical procedure to evaluate inside the body using an endoscope, an instrument composed of a thin tube with an eyepiece at one end and a light and camera at the other end. The endoscope is used for direct visual examination of the esophagus, stomach, and small intestine. In some cases, the veterinarian will remove a foreign body if present or obtain biopsy samples for further evaluation.
- Colonoscopy: Similar to gastroscopy, a colonoscopy is an evaluation of the colon using an endoscope.
- Upper gastrointestinal barium series: Barium sulfate, a white radio-opaque metallic powder, is administered via syringe into the cheek pouch, once swallowed, the barium coats the inside walls of the gastrointestinal tract, which shows up the structures as bright white on the x-ray. The veterinarian can also monitor the transit time of the barium during this procedure.
- Abdominal x-ray: A non-invasive diagnostic procedure in veterinary medicine to see inside the body which uses a type of radiation called electromagnetic waves, which allows the veterinarian to assess for possible tumors or foreign bodies as well as evaluate the size and shape of the kidneys and liver.
- Ultrasound: A test that uses high-frequency sound waves to capture live images from inside the body to evaluate the size and shape of the liver and kidneys and evaluate the gastrointestinal tract.
- Fecal examination: To evaluate for the presence of parasite eggs
Recovery of black cat poop
The recovery and outcome of black cat poop will depend on the underlying cause. Moderate to severe cases of melena may require hospitalization to stabilize the cat, followed by home care while the cat recovers.
Once treatment begins, black stools should return to normal within a few days. If the cause of black cat poop can be treated and cured, the outcome is excellent. Some conditions may not be cured but are able to be managed to slow down their progress.
The outcome for cats who have ingested a poison depends on the amount and the duration of exposure. Prompt veterinary attention is critical to prevent further absorption and organ damage.
In most cases, follow-up appointments will be necessary to repeat bloodwork and monitor your cat’s progress.
Related post: Bloody Mucus or Jelly in Cat Poop.