Old Dog Diarrhea: When to Worry and What to Do

Seniors dehydrate fast. Learn which diarrhea signs need a vet today, common causes in older dogs and how to help at home with your vet's OK.

Call your vet the same day if your senior dog's diarrhea has blood, looks black and tarry, comes with vomiting, weakness or no appetite, or lasts more than a day or two. Older dogs dehydrate faster, and VCA lists senior dogs among those who should see a vet sooner. For one soft stool in a dog who is bright and eating, keep water close and ask your vet for a feeding plan.

Quick take: Ask your vet about a veterinary probiotic such as Purina FortiFlora, which the maker labels for the dietary management of dogs with diarrhea.

When to worry

Sign	How urgent
Blood, black tarry stool, or diarrhea with repeated vomiting	Same day or emergency
Weakness, collapse, pale gums or a painful belly	Emergency
Not eating or not drinking	Same day
Diarrhea lasting more than 24 to 48 hours	Same day or next day
One or two soft stools, dog otherwise normal	Call for advice and watch closely

Common causes in older dogs

• Eating something new, spoiled or from the trash
• A sudden change of food or treats
• Stress, such as boarding or a move
• Parasites such as giardia, which affect seniors too
• Medicines, including some antibiotics
• Pancreatitis
• Kidney, liver or bowel disease, including tumors, which become more common with age

How to help at home

Do this with your vet's OK, especially if your dog has kidney disease, diabetes or another condition.

• Keep fresh water within reach and offer small amounts often
• Ask your vet before holding back food
• Feed small meals of the bland or prescription diet your vet suggests
• Switch back to the regular food slowly over 7 to 10 days
• Ask your vet about a veterinary probiotic
• Save a fresh stool sample in a bag in case your vet wants a fecal test
• Clean accidents with an enzyme cleaner so the smell does not draw your dog back

Skip human medicines. The AKC warns that Pepto-Bismol and Imodium can be harmful for some dogs, so use them only if your vet says so.

What your vet may check

A fecal test for parasites, blood work for kidney, liver and pancreas problems, and sometimes X-rays or an ultrasound. Bring notes on when it started, how often it happens, what the stool looks like and anything your dog ate.

Shop the picks

• Purina Pro Plan Veterinary FortiFlora: probiotic powder the maker labels for puppies and adult dogs with diarrhea. Check with your vet first.
• Rocco & Roxie Enzyme Stain & Odor Eliminator: enzyme cleaner for accidents on carpet and floors.

FAQ

How long is too long for diarrhea in an old dog?

More than a day or two needs a vet, and so does any diarrhea with blood, vomiting or weakness. Seniors can dehydrate quickly.

Can I give my senior dog Pepto-Bismol or Imodium?

Not without your vet's advice. The AKC warns that some human medicines can harm dogs.

Is chicken and rice good for an old dog with diarrhea?

Ask your vet first. Some seniors have kidney disease or other conditions that need a specific diet.

Should I worry about diarrhea with blood in an old dog?

Yes. Call your vet the same day, and go to an emergency clinic if your dog is weak, vomiting or passing black, tarry stool.

Sources: VCA: Diarrhea in dogs, AKC: Dog diarrhea, Merck Veterinary Manual: GI ulcers.

Related guides: Old dog vomiting: when to worry, Probiotics and senior gut health, Senior dog constipation.

Educational only, not a substitute for your veterinarian. As an Amazon Associate we earn from qualifying purchases.

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