Melena in Cats: What It Means
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Melena in cats refers to black, tarry, foul-smelling stool caused by digested blood from the upper gastrointestinal tract.
Updated: 2026-07-31
Quick Answer
Melena in cats is black, tarry stool caused by digested blood from the upper gastrointestinal tract, such as the stomach or small intestine. It can result from stomach ulcers, intestinal bleeding, or certain medications. Melena should be treated as potentially serious. Contact a veterinarian promptly, especially if accompanied by weakness, vomiting, or appetite loss.
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What This May Mean
Melena in cats refers to black, tarry, foul-smelling stool caused by digested blood from the upper gastrointestinal tract. The blood originates from the stomach or small intestine and turns black as it is digested during passage through the digestive tract. Melena is a significant finding that warrants prompt veterinary evaluation.
Cats are obligate carnivores, and their stool reflects diet, hydration, and digestive health. Because most cats use litter boxes, owners have a regular opportunity to observe stool color, consistency, and frequency. Changes in litter box habits or stool appearance can sometimes be the first sign of a health issue, which is why paying attention to what is normal for your cat is important.
Possible Causes
Several factors may contribute to this stool appearance in cats. A veterinarian can help determine which are relevant for your cat.
- Upper gastrointestinal bleeding from stomach ulcers or inflammation
- Intestinal bleeding from foreign bodies, tumors, or inflammatory disease
- Ingestion of blood from grooming wounds or oral and nasal bleeding
- Certain medications that irritate the stomach lining, including some anti-inflammatory drugs
- Clotting disorders or systemic conditions that cause gastrointestinal bleeding
Keep in mind that stool changes can result from more than one factor at the same time. A veterinarian can perform a physical exam, fecal testing, blood work, or imaging to narrow down the cause. Avoid making assumptions based on appearance alone, since different conditions can produce similar stool changes.
Home Observation
When monitoring this change at home, the following details can help you and your veterinarian assess the situation:
Note the color (jet black vs. dark brown), texture (tarry vs. firm), and odor of the stool. Check for weakness, pale gums, vomiting (especially coffee-ground material), appetite loss, collapse, or abdominal pain. Take a photo and record any recent medication or dietary changes.
Litter Box Monitoring Tips
- Scoop the litter box at least once daily so you can notice changes promptly
- Note the number of stool clumps, their size, color, and consistency each day
- Take a clear photo of unusual stool so you can show your veterinarian
- Track whether your cat is spending more or less time in the litter box than usual
- Keep a simple log of dates, dietary changes, and any other symptoms
When to Contact a Veterinarian
Melena should be treated as potentially serious. Contact a veterinarian promptly. Seek urgent care if melena is accompanied by weakness, pale gums, vomiting blood or coffee-ground material, appetite loss, collapse, or abdominal pain. Kittens, seniors, and cats with existing illness are at higher risk.
Signs that warrant urgent veterinary attention include:
- Large amounts of blood in the stool or dark, tarry stool
- Repeated vomiting, especially with blood or coffee-ground material
- Severe lethargy, collapse, or weakness
- Pale gums or signs of dehydration (sunken eyes, dry gums, skin tenting)
- Abdominal pain, swelling, or distress
- No stool production for more than two days with straining
Kittens, senior cats, and cats with existing medical conditions are at higher risk of complications and should be evaluated promptly.
If you are unsure whether the situation is urgent, calling a veterinary clinic for guidance is a reasonable step. Many clinics can advise you over the phone on whether your cat should be seen immediately or can wait for a scheduled appointment. Having a photo of the stool and a record of when changes started can help the veterinary team triage the situation.
Frequently Asked Questions
What does melena look like in cats?
Melena appears as jet black, sticky, tarry stool with a distinctly strong, foul odor. It is different from normal dark brown stool, which is firm and not unusually smelly. A veterinarian can perform a fecal test to confirm the presence of blood.
Is melena in cats an emergency?
Melena can indicate significant gastrointestinal bleeding and should be evaluated by a veterinarian promptly. Seek urgent care if it is accompanied by weakness, pale gums, vomiting blood, appetite loss, collapse, or abdominal pain. Do not wait if these signs are present.
POOP SCANNER
Describe what you see and get a prioritized, evidence-based assessment of possible causes.
This tool provides general information and does not replace a veterinarian's diagnosis.
Sources
- Cornell Feline Health Center, Cornell University College of Veterinary Medicine
- VCA Hospitals, Veterinary Clinical Articles
- Merck Veterinary Manual, Merck & Co., Inc.
Disclaimer
This article and the PawAI Poop Scanner tool provide general information and do not replace examination, diagnosis, or treatment by a licensed veterinarian. If your cat shows concerning signs, contact a veterinarian.