Do Dogs Get Hemorrhoids? Causes of Rectal Bleeding
By Dr. Zubair Khalid, DVM, MS, PhD ·
Do dogs get hemorrhoids? True hemorrhoids are rare in dogs. The swollen, itchy veins that cause hemorrhoids in people are not a common problem in the canine rectum. When a dog bleeds from the rear end, the cause is usually something else, and finding that cause matters more than the label. This article is educational and is not a substitute for veterinary diagnosis or treatment.
Quick Answer
- True hemorrhoids are uncommon in dogs. Most rectal bleeding has a different cause.
- Anal sac disease is the most common disease of the anal region in dogs [1].
- Fresh red blood on the stool or on the fur usually points to a problem in the lower bowel or anus.
- Some causes are mild and self-limiting, while others need same-day care.
- Any dog with heavy bleeding, pain, or repeated straining should see a veterinarian.
Can Dogs Have Hemorrhoids?
What Hemorrhoids Are in People
In humans, hemorrhoids are swollen veins in the lower rectum and anus. They can itch, hurt, and bleed. The problem comes from pressure and straining on those veins over time.
Why Dogs Rarely Get Them
Dogs have a different anatomy in that area. They also do not sit on a toilet or strain upright the way people do. Because of this, veterinarians rarely diagnose hemorrhoids in dogs. When an owner sees blood near a dog's bottom, the real cause is almost always something else.
What Causes Dog Hemorrhoids? (And What Usually Causes the Bleeding)
Owners often search for "what causes dog hemorrhoids" when they really mean "why is my dog bleeding back there." Here are the conditions veterinarians actually find.
Anal Gland Problems
Anal sacs sit on each side of the anus. They make a small amount of foul-smelling liquid that is normally squeezed out during a bowel movement [1]. These sacs can become clogged, infected, abscessed, or cancerous [1]. Anal sac disease is the most common disease of the anal region in dogs [1]. Small breeds are more prone to it, while large and giant breeds are rarely affected [1].
Common reasons the sacs clog include failure of the sacs to empty during defecation, poor muscle tone in obese dogs, and too much gland secretion [1]. When the contents build up, bacteria can overgrow and cause infection and inflammation [1].
Rectal Tears and Trauma
A tear in the lining of the rectum can cause bleeding. These tears come from sharp bones, needles, or other rough material passing through [2]. Bite wounds and trauma from rectal palpation are other causes [2]. Straining and bleeding are the most common signs [2]. Partial tears in dogs may heal with medical care, but full-thickness tears usually need surgery [2].
Colitis and Severe Diarrhea
Inflammation of the colon can produce fresh blood and mucus in the stool. One report described a dog with acute bloody diarrhea caused by a rare bacterium called Brachyspira hyodysenteriae, along with other gut infections [3]. That dog recovered fully after treatment [3]. This shows how many different germs and conditions can lead to bloody stool.
Growths, Polyps, and Rare Conditions
Some young dogs develop unusual growths in the colon. One 4-month-old puppy had chronic bloody stool, repeated rectal prolapse, and straining, and was found to have a rare mass called colonic hamartomatous ganglioneuromatosis [4]. Surgery removed the affected colon, and about a year later the puppy appeared normal [4]. Growths like polyps are uncommon but are on the list of reasons a dog bleeds from the rectum.
Other Body-Wide Causes
Bleeding can also come from problems outside the gut. A study of dogs recovering from neck spine surgery found that 23% had stomach or intestinal signs, including bloody stool in some cases [5]. Most of those signs lasted only 1 to 2 days [5]. This reminds us that rectal bleeding is sometimes a side effect of stress, medication, or another illness.
A Note on Procedures
Even medical care can rarely cause problems. One dog developed a narrowing of the colon weeks after a rectal catheter was used during treatment for severe bloody diarrhea [6]. This is an uncommon complication, but it shows why ongoing signs after a procedure deserve a vet visit.
If your dog has blood in the stool but seems fine otherwise, see Dog Blood in Stool but Acting Normal: What Does It Mean?. For a deeper look at the main patterns of rectal bleeding, read Why Is My Dog bleeding from rectum? HGE vs Colitis vs Polyps.
Signs Owners Notice
Watch for these clues. They help your vet narrow down the cause.
| Sign | What it often points to |
|---|---|
| Bright red blood on stool surface | Lower bowel or anal problem |
| Blood and mucus together | Colitis or infection |
| Scooting or licking the rear | Anal sac discomfort |
| Straining to poop | Anal sac disease, tear, or mass |
| Foul smell near the rear | Anal sac infection or abscess |
| Diarrhea with blood | Gut infection or inflammation |
| Weight loss or vomiting | More serious or body-wide disease |
Some dogs show only one sign. Others show several at once. The pattern and duration matter as much as the bleeding itself.
How Veterinarians Diagnose the Problem
Physical Examination
The first step is a full exam. Your vet will look at the anus and feel the anal sacs. For rectal tears, diagnosis is based on physical examination [2]. This simple step often finds the answer.
Rectal and Fecal Tests
Your vet may check a stool sample for parasites, bacteria, and blood. In the dog with the rare bacterial infection, standard fecal tests were negative, and a special PCR test found the germ [3]. This shows that some causes need targeted testing.
Imaging and Biopsy
If the exam points to a mass or a deeper problem, imaging can help. The puppy with the colonic mass was diagnosed with abdominal imaging before surgery [4]. In another case, ultrasound and CT confirmed an unusual stomach problem in a dog with bloody stool [7]. A biopsy gives a definite answer when a growth is found.
Treatment Options
Treatment depends on the cause. Your veterinarian will set the plan for your dog.
Anal Sac Care
Clogged sacs are often emptied by hand. Infected or abscessed sacs may need antibiotics, pain relief, or flushing. Your vet calculates any dose from your dog's weight and health.
Diet and Gut Support
Colitis and diarrhea often improve with a bland or prescription diet, fluids, and time. Some dogs need medications to calm inflammation or treat infection. The dog with the rare bacterial infection improved after a course of antibiotics and a dewormer [3].
Surgery
Full-thickness rectal tears usually need surgical repair [2]. Masses in the colon may also be removed with surgery, as in the puppy with the rare growth [4]. Some procedures can be done with an endoscope instead of open surgery, as in the dog whose stomach problem was corrected without an operation [7].
Hospital Care
Dogs with severe bloody diarrhea may need intravenous fluids and monitoring. In one report, a dog with acute hemorrhagic diarrhea syndrome was hospitalized for supportive care and recovered enough to go home 5 days later [6]. Hospital care is reserved for dogs who are very ill.
Recovery, Outlook, and Long-Term Management
The outlook varies widely by cause.
- Anal sac disease often responds well to treatment, but some dogs need repeat care.
- Partial rectal tears in dogs may heal with medical management [2].
- Most stomach and intestinal signs after spine surgery lasted only 1 to 2 days [5].
- The puppy with the rare colonic growth appeared normal about a year after surgery [4].
- The dog with the rare bacterial infection recovered fully after treatment [3].
Some dogs need lifelong diet changes or regular checkups. Others recover and never have another episode. Your vet will tell you what to expect for your dog's specific problem.
Prevention
You cannot prevent every cause of rectal bleeding, but you can lower the risk.
- Keep your dog at a healthy weight. Poor muscle tone in obese dogs plays a role in anal sac clogging [1].
- Feed a balanced diet and avoid sharp bones or objects that could tear the rectum [2].
- Treat diarrhea early instead of waiting for it to worsen.
- Keep up with parasite prevention and routine exams.
- Watch for scooting, licking, or straining, and call your vet if these continue.
If your dog has blood in the stool along with urgency or repeated trips outside, see Blood in dog stool causes urgency and veterinary evaluation. Blood in urine is a different problem and is covered in Why Is My Dog having bloody urine? Cystitis Bladder Stones and UTI Guide.
Limitations and When to Contact a Veterinarian
This article cannot tell you what is wrong with your dog. Only a veterinarian who examines your dog can do that. Individual cases need a veterinarian, and the timing matters.
Call your veterinarian the same day if you see:
- More than a few drops of fresh blood
- Blood mixed with large amounts of mucus
- Repeated straining with little or no stool
- Scooting or licking that does not stop
- A foul smell or swelling near the anus
Go to an emergency clinic now if you see:
- Heavy or nonstop bleeding
- A large amount of blood in the stool
- Weakness, collapse, or pale gums
- Vomiting with blood or a black, tarry stool
- Severe pain when you touch the rear end
- A suspected object or bone stuck near the anus
Schedule a routine visit if the bleeding is small, happens once, and your dog is eating, drinking, and acting normal. Even then, a checkup is wise, because some causes start quietly.
Frequently Asked Questions
Can dogs have hemorrhoids?
True hemorrhoids are rare in dogs. The veins and tissues in that area do not develop the same problem people get. If your dog is bleeding from the rear, a veterinarian will look for other causes first.
What causes dog hemorrhoids?
Since real hemorrhoids are uncommon, most owners are really asking about rectal bleeding. The usual causes include anal sac disease, rectal tears, colitis, infections, and growths. Anal sac disease is the most common disease of the anal region in dogs.
Is dog rectal bleeding an emergency?
It depends on how much blood you see and how your dog acts. A few drops with normal behavior can wait for a routine visit. Heavy bleeding, weakness, or pain needs emergency care right away.
How do I know if my dog has an anal gland problem?
Common signs include scooting, licking the rear, a foul smell, and straining to poop. Your vet can check the sacs during a simple exam. Small breeds are more likely to have this problem.
Can rectal bleeding in dogs go away on its own?
Some mild cases do improve without treatment, especially brief bouts tied to stress or a minor upset. Others get worse without care. Because you cannot tell the difference at home, have your dog checked if bleeding lasts more than a day or comes back.
Related Articles
- Why Is My Dog bleeding from rectum? HGE vs Colitis vs Polyps
- Dog Blood in Stool but Acting Normal: What Does It Mean?
- Dog Scratching Ears Making Them Bleed
- Why Is My Dog having bloody urine? Cystitis Bladder Stones and UTI Guide
- Blood in dog stool causes urgency and veterinary evaluation
- Why Is My Dog vomiting blood? Hemorrhagic Gastroenteritis Emergency
- Dog Hemorrhoids or Anal Gland Trouble? What to Do
- Blood Clots in Dog Poop: Causes and What to Do
- Why Is My Dog's Poop Like Jelly With Blood?
References
- Disorders of the Rectum and Anus in Dogs - Dog Owners. Merck Veterinary Manual.
- Rectal Tears in Animals - Digestive System. Merck Veterinary Manual.
- Brachyspira hyodysenteriae detected in a dog with acute haemorrhagic diarrhoea: a case report. BMC veterinary research, 2026.
- Colonic Hamartomatous Ganglioneuromatosis in a 4 Mo Old Puppy. Journal of the American Animal Hospital Association, 2023.
- Gastrointestinal complications occur in dogs with intervertebral disk herniation undergoing ventral slot decompression but are mostly self-limiting. Journal of the American Veterinary Medical Association, 2026.
- Colonic Stricture Formation in a Dog Treated for Acute Hemorrhagic Diarrhea Syndrome With a Rectal Foley Catheter. Journal of veterinary emergency and critical care (San Antonio, Tex. : 2001), 2025.
- Endoscopic reduction of true gastrogastric intussusception in a dog. Journal of veterinary internal medicine, 2026.