Blood in Your Cat’s Stool: What Does it Mean?

Noticing blood in your cat’s litter box can be quite alarming. While some causes are minor and easily treatable, others may signal a more serious medical condition that needs prompt attention — and devoted pet parents can be left unsure what to do next.  

Because bloody stools can be a symptom of anything from temporary gastrointestinal irritation to a life-threatening illness, it’s important to investigate the underlying cause. In the meantime, your cat’s behavior and the color and consistency of the stool can help you determine whether the situation warrants a trip to the emergency vet or just the next available office visit. 

Common Causes of Bloody Stools in Cats

Minor Causes

The reason behind your cat’s alarming bowel movement may be relatively benign. The problem can stem from: 

• Dietary issues: Cats are curious eaters, but often highly sensitive to change. If you’re trying out a new brand of kibble or they gain access to unattended human food, intestinal irritation may result. This can sometimes lead to small amounts of blood in their stool following ingestion.
• Mild gastrointestinal irritation: Environmental stress or minor colitis (inflammation of the colon) can result in temporary bleeding.
• Rectal or anal trauma: Constipation and impacted stool from dehydration or medications can cause small tears in the rectum during defecation. Issues with anal glands may also leave traces of blood.

Serious Causes

While the explanation for your cat’s bloody stool is hopefully a simple one, it’s important to rule out other medical conditions that require expeditious treatment. 

• Parasites: Hookworms, roundworms, or coccidia can cause intestinal bleeding.
• Infections: Bacterial or viral infections of the GI tract may lead to diarrhea with blood.
• Inflammatory Bowel Disease (IBD): Chronic inflammation in the intestines can cause recurring bleeding.
• Food allergies or intolerances: Some cats react to certain proteins or ingredients, which can irritate the gut.
• Polyps or tumors: Benign or cancerous growths in the intestines can cause bleeding, sometimes intermittently.
• Coagulopathy: Blood clotting disorders or ingestion of toxins (like rat poison) may result in visible blood in the stool. If left untreated, coagulopathy can lead to life-threatening hemorrhaging or thrombosis. 

What the Color of Bloody Stools Can Tell You

Though it won’t reveal the root of the problem, the appearance of the blood in your cat’s stool can offer important clues about where the bleeding originates. This information will be very helpful to your veterinarian in arriving at a diagnosis, so it’s a good idea to take a picture if possible. 

Bloody stools generally fall into two categories: 

Bright red blood (hematochezia): Fresh blood typically comes from the lower GI tract, including the colon, rectum, or anus. Hematochezia usually points to gastrointestinal irritation, anal gland issues, colitis, or rectal trauma.

Dark, tarry stool (melena): Deep red blood and sticky, foul-smelling stool indicate bleeding in the upper GI tract, including the stomach or small intestine. It’s a possible indicator of more serious issues like ulcers, tumors, or systemic illness.

Keep in mind that the color of the blood only points to the location of the bleeding, not the cause. While fresh blood is generally less worrisome, it still warrants an examination from your vet. 

Other Symptoms to Watch For

Your cat’s overall health and behavior can provide important context for bloody stools. Don’t ignore: 

• ​​Vomiting, especially if it is frequent or if blood is present.
• Lethargy or weakness, which can signal anemia or other illnesses.
• Loss of appetite or weight loss. Persistent changes may indicate chronic digestive problems.
• Diarrhea or constipation. Changes in stool consistency can help pinpoint GI tract issues.
• Straining or signs of pain during defecation that indicate rectal or anal issues.
• Behavioral changes, like hiding, irritability, or decreased grooming. 

If your cat exhibits any combination of these symptoms along with blood in the litterbox, seek veterinary care quickly.

What to Expect at the Vet

In order to determine the cause of the bleeding, your vet will perform a thorough physical examination, checking your cat’s abdomen, rectal area, and overall health. From there, diagnostic tests like fecal exams, bloodwork, imaging, or biopsies can provide more definitive answers. 

Once you know why the bloody stools are occurring, you can support your cat with the recommended medications or lifestyle changes. 

What to Do in the Meantime

If your cat isn’t exhibiting any additional worrisome symptoms and your vet agrees that they can wait to be seen, good home care can help shorten their road to recovery. 

Here are a few ways to help your cat while you wait for your appointment: 

• Keep a stool log. Note color, frequency, and consistency to help your vet identify patterns.
• Monitor diet. Avoid sudden changes and prevent access to table scraps or trash.
• Avoid medications without guidance. Over-the-counter treatments may worsen the problem, so check with your vet before introducing anything new. 
• Provide a calm environment. Stress can trigger or exacerbate GI issues in cats.

Remember, your observations are a valuable part of your cat’s care. The more detailed information you can provide, the easier it is for your veterinarian to make an accurate diagnosis and get your cat the right treatment.