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Acute Diarrhea in Dogs: When to Worry and What to Feed

Diarrhea is common in dogs but can indicate something serious. Learn when it's an emergency and how to manage it at home.

Acute Diarrhea in Dogs: When to Worry and What to Feed

Acute diarrhea — sudden onset of loose, watery stools — is one of the most common reasons dogs visit the vet. Most cases are caused by dietary indiscretion (eating something they shouldn't) and resolve within 1-2 days. However, some cases need immediate veterinary attention.

  • Most acute diarrhea is caused by dietary indiscretion
  • Bland diet (boiled chicken + rice) helps settle the stomach
  • Keep your dog hydrated — diarrhea causes fluid loss
  • Bloody diarrhea is always a vet emergency
  • Puppies with diarrhea need vet attention quickly
  • If diarrhea lasts more than 48 hours, see your vet

Common Causes

The most common cause is eating something unusual — garbage, table scraps, a new food, or something from outside. Other causes include bacterial infections (Salmonella, E. coli), viral infections (parvovirus in unvaccinated puppies), parasites (Giardia, roundworms), food allergies, stress, and medication side effects.

Home Management

For mild diarrhea in an otherwise alert, eating dog: fast for 12 hours (water only), then introduce a bland diet of boiled chicken breast (no skin, no seasoning) and white rice in a 1:2 ratio. Feed small, frequent meals. Gradually transition back to regular food over 3-4 days. Ensure fresh water is always available.

When It's an Emergency

Rush to the vet if you see: blood in the stool (bright red or black/tarry), diarrhea with vomiting, lethargy or collapse, a puppy with diarrhea (they dehydrate quickly), diarrhea lasting more than 48 hours, suspected toxin ingestion, or if your dog is also not drinking water.

Prevention

Keep garbage secured, don't change food suddenly (transition over 7-10 days), avoid giving table scraps, keep your dog's vaccinations and deworming up to date, and supervise outdoor time to prevent scavenging.

  • Blood in the stool (red or black)
  • Diarrhea with vomiting
  • Lethargy, weakness, or collapse
  • A puppy with diarrhea
  • Diarrhea lasting more than 48 hours
  • Your dog won't eat or drink

RVC

RVC can quickly diagnose the cause of diarrhea through fecal testing, blood work, and imaging if needed. We provide IV fluids for dehydration, anti-nausea medication, and targeted treatment. Walk-ins welcome for urgent cases — call +853 6677 6611.

+853 6677 6611

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