Constipation in dogs is less common than diarrhoea and more likely to indicate something underlying. It is also easy to confuse with a far more serious problem, which is the main reason to pay attention to it.
What counts as constipation
Most dogs pass stool once or twice a day. Occasionally missing a day is not automatically a problem, particularly if the dog is otherwise well.
Constipation means difficulty passing stool, infrequent passage, or stools that are abnormally hard and dry. Obstipation is severe constipation where the dog cannot pass anything at all.
Signs:
- Straining, adopting the position repeatedly and producing little or nothing
- Hard, dry, small, pellet-like stools
- Stool coated in mucus or streaked with fresh blood from straining
- Reduced appetite
- Lethargy, discomfort, a hunched posture
- Vomiting in more advanced cases
- Repeated visits to the garden with no result
Common causes
Dehydration. The colon reabsorbs water from stool. A dog that is not drinking enough produces dry, hard stools. This is the single most common contributor.
Dietary. Too little fibre, or sometimes too much. Sudden diet changes. Low food intake generally.
Eating things that should not be eaten. Bones are the classic culprit — cooked bones especially produce hard, chalky, painful stools. Also hair, grass, fabric, soil, cat litter.
Lack of exercise. Movement stimulates gut motility.
Ignoring the urge. Dogs that are not let out often enough, or that will not toilet in an unfamiliar place while boarding or travelling.
Pain. A dog with arthritis, anal gland problems, a back problem or a perianal wound may avoid the posture because it hurts. This is very common in older dogs and often missed.
Medications. Some painkillers, antihistamines, diuretics and iron supplements.
Prostate enlargement in unneutered male dogs, pressing on the rectum.
Perineal hernia, more common in older unneutered males.
Neurological problems affecting the nerves controlling the colon.
Masses or strictures narrowing the passage.
Megacolon, where the colon loses its ability to contract effectively. Uncommon in dogs but serious.
When to see a vet
Straight away:
- No stool for more than 48 to 72 hours
- Repeated straining producing nothing
- Vomiting alongside constipation
- Obvious pain, distress or a distended abdomen
- Blood in significant quantity
- Lethargy or refusal to eat
- Any uncertainty about whether it is stool or urine the dog cannot pass
- A dog that may have eaten bones, a toy, fabric or anything obstructive
Book an appointment:
- Recurring constipation
- An older dog whose pattern has changed
- Straining that has been going on for a day or more
- An unneutered male dog with difficulty passing stool
What is safe to try at home for mild cases
Only for a dog that is otherwise well, eating, bright and has been constipated for less than a day or two.
Water
Increase intake every way you can. Add water to food, offer wet food, put more bowls around the house, use a small amount of unsalted stock to make water more appealing.
XIAZ Elevated Dog Bowl Stand
Older and arthritic dogs often drink less simply because lowering the head is uncomfortable — which is precisely the group most prone to constipation.
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Fibre
Plain tinned pumpkin — not pie filling, which contains spices and sugar — is the standard suggestion. A teaspoon for a small dog up to a couple of tablespoons for a large one, mixed into food.
Psyllium husk is also used, but doses matter and it must be given with plenty of water, so ask your vet first.
Exercise
A walk stimulates the gut. Even a gentle amble helps, and it also gives more opportunity to go.
Time and opportunity
Some dogs simply need more chances. Take the dog out more often, to the place it usually chooses, and stand quietly rather than watching expectantly.
Comfort
If pain is the barrier — an arthritic dog that cannot hold the posture — the answer is pain relief from your vet, not a laxative. Non-slip flooring and a soft surface to toilet on also help.
What not to do
- No human laxatives. Doses and formulations are wrong and several are toxic.
- No mineral oil or liquid paraffin by mouth. Risk of inhalation into the lungs, which causes a severe pneumonia.
- No milk. The “milk loosens things” idea causes diarrhoea in lactose-intolerant dogs rather than resolving constipation.
- No manual intervention. Do not attempt to remove anything yourself.
- No bones. Whatever the internet says, bones are a leading cause of constipation, not a treatment.
What your vet will do
History and physical examination, including a rectal examination to assess the stool, the prostate and the pelvic canal. X-rays to see how much stool is present and to look for obstruction, bone fragments or pelvic abnormalities. Bloods to check hydration, electrolytes, kidney function and thyroid.
Treatment may include fluids, prescription laxatives or stool softeners, an enema under sedation, pain relief, and treatment of whatever underlying cause is found. Severe cases occasionally require manual evacuation under anaesthetic.
Prevention
- Constant access to fresh water
- Consistent, appropriate diet with adequate fibre
- Regular exercise
- Frequent toilet opportunities — never make a dog wait eight or ten hours
- No bones
- Manage arthritis pain properly in older dogs
- Keep long coats trimmed around the rear, since matted hair can physically block passage
- Regular anal gland checks if your dog has a history of problems
Purina FortiFlora Canine Probiotic Supplement
Often used to support gut health, particularly after antibiotics or a digestive upset. It is a supportive measure rather than a treatment for constipation — ask your vet whether it fits your dog’s situation.
The short version
One missed day in a well dog: watch, add water, take a walk. Two days, or any straining with distress, vomiting or a dog that seems unwell: ring the vet. And if you cannot tell whether the dog is trying to pass stool or urine, do not wait to find out.
