This page focuses on urgent assessment. Routine wellness exams, preventive care, and monitoring of stable conditions are provided through scheduled general wellness appointments.

Dog Vomiting and Diarrhea for Over 24 Hours – What It Means and When to Act

Vomiting and diarrhea lasting more than 24 hours in dogs can range from dietary upset to life-threatening systemic illness, depending on the underlying cause and progression.

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Definition

Vomiting and diarrhea are clinical signs, not diagnoses. They refer to the forceful expulsion of stomach contents and loose, frequent stools, respectively.

When both occur together for over 24 hours, it signals that the gastrointestinal tract or other internal systems may be involved. Causes can range from food reactions and infections to endocrine disorders, toxin exposure, or internal organ dysfunction.

Persistent vomiting and diarrhea in dogs often indicate deeper systemic illness and cannot be assessed by symptoms alone.

Who This Page Is For

Dogs vomiting and having diarrhea for more than 24 hours
Dogs that have stopped eating or drinking during that time
Dogs with visible blood in stool or vomit
Dogs appearing tired, dehydrated, or weak
Dogs that initially improved but worsened again

Who This Page Is Not For

Dogs who vomited once and have had a single loose stool but are otherwise eating, drinking, and acting normal

If you are unsure whether this is significant, that uncertainty itself warrants veterinary assessment.

Related Urgent Symptoms

Dog Vomiting – Causes, When to Worry, What to Do
Dog Has Diarrhea – What’s Normal vs Dangerous
Dog Vomiting Blood – Emergency Signs You Should Not Ignore
Dog or Cat Vomiting and Diarrhea at the Same Time
Dog Lethargic and Weak – Signs of Serious Illness
Dog Not Eating – When to Worry and What to Do
Dog or Cat Suddenly Weak, Lethargic, or Collapsing
Swollen or Bloated Belly in Cats

What This Can Look Like at Home

Vomiting and diarrhea may be frequent, messy, or show traces of blood. Your dog may avoid food and water, seem lethargic, or hide.

Repeated vomiting with or without food present
Loose, watery, or foul-smelling stool
Straining with diarrhea or urgency to go out
Blood or mucus in stool or vomit
Dry nose, sunken eyes, or skin tenting (dehydration signs)
Refusal to eat or drink for more than 24 hours

Why This Can Be Hard to Judge

Vomiting and diarrhea often look similar regardless of cause. Some dogs still seem playful or eat treats despite dehydration or internal illness. Episodes may appear to taper off, then return. Owners may underestimate severity when symptoms appear intermittent.

Apparent improvement or energy does not mean the condition has resolved.

The Improvement Trap

Some dogs improve briefly due to slowed gut motility or temporary fasting, then worsen again as inflammation or toxin buildup returns. This cycling pattern is especially common with infections, pancreatitis, and foreign body obstructions.

What Is Easy to Miss at Home

Early dehydration
Abdominal pain or bloating
Weight loss or body condition change over days
Blood streaks in stool or vomit
Subtle signs of shock (cold ears, weak pulse, pale gums)
Worsening lethargy or trembling

Even when vomiting and diarrhea seem mild, these signs may reflect internal instability.

When This Can Be an Emergency

Some dogs can deteriorate quickly once fluid loss overwhelms their body’s ability to compensate.

No food or water intake for more than 24 hours
Vomiting and diarrhea happening more than 3 times in 24 hours
Blood in stool or vomit
Vomiting water immediately after drinking
Visible signs of pain (panting, trembling, restlessness)
Gums pale, sticky, or dry
Acting confused, collapsed, or severely lethargic
History of toxin exposure, pancreatitis, or recent dietary indiscretion

How Veterinarians Assess This

Clinical signs alone cannot reliably determine severity.

Symptoms can appear similar while representing very different internal disease processes. Diagnostic testing is how veterinarians determine whether a condition is mild and self-limiting or serious and potentially life-threatening, and how they guide appropriate care.

Diagnostic testing may include:

Bloodwork (CBC, biochemistry profile) to assess organ function and hydration
Electrolyte panel to evaluate for imbalances
Fecal testing to screen for parasites or bacterial overgrowth
Pancreatic enzyme testing (PLI) to rule out pancreatitis
Abdominal radiographs (x-rays) to identify obstruction or gas patterns
Abdominal ultrasound to visualize gut wall, lymph nodes, and internal organs

Additional disease-specific testing (such as ACTH stimulation, parvovirus antigen, toxin screening, or biopsies) may be considered based on the overall clinical picture.

Veterinary Differentials - Serious / Must-Rule-Out First

Gastrointestinal obstruction. Blockage in the intestines or stomach can cause persistent vomiting and diarrhea.Tests may include radiographs, ultrasound, bloodwork.
Parvovirus infection. A serious viral illness especially in unvaccinated dogs, often causing bloody diarrhea and vomiting.Tests may include parvo antigen testing, bloodwork, electrolyte panel.
Hemorrhagic gastroenteritis (AHDS). A condition causing sudden bloody diarrhea and vomiting with rapid fluid loss.Tests may include CBC, biochemistry panel, fecal testing.
Pancreatitis. Inflammation of the pancreas can trigger vomiting, diarrhea, and loss of appetite.Tests may include pancreatic lipase (PLI), bloodwork, ultrasound.
Toxin ingestion. Ingesting human medication, spoiled food, or toxins can result in gastrointestinal and systemic illness.Tests may include bloodwork, toxin panel, imaging.

Veterinary Differentials - Common / More Typical

Dietary indiscretion. Eating something inappropriate such as garbage, fatty food, or spoiled meat.Tests may include bloodwork, abdominal imaging.
Parasitic infection. Worms such as hookworms, roundworms, or whipworms can cause GI upset.Tests may include fecal flotation, fecal antigen panel.
Bacterial gastroenteritis. Infections with Clostridium, Salmonella, or E. coli may cause vomiting and diarrhea.Tests may include fecal PCR panel, culture.
Inflammatory bowel disease. Chronic inflammation of the gut can cause intermittent vomiting and diarrhea.Tests may include bloodwork, ultrasound, GI panel.
Non-specific gastritis or enteritis. Mild, self-limiting irritation of the GI tract from unknown or transient cause.Tests may include supportive care trial, bloodwork.

Safety, Psychology, & Peace of Mind

Dogs can lose significant fluid and electrolytes even when vomiting or diarrhea appear mild. Internal disease can progress before outward symptoms change. Diagnostic testing offers clarity, prevents complications, and supports a faster, safer recovery. Timely care also reduces risk of recurrence.

Frequently Asked Questions

Is vomiting and diarrhea for more than 24 hours an emergency?

It can be. Persistent vomiting and diarrhea can lead to dangerous dehydration, electrolyte loss, or reveal a deeper illness. If your dog hasn’t eaten, kept water down, or is worsening after a day, urgent care is advised.

My dog looks fine despite having diarrhea — should I still worry?

Yes. Dogs may seem energetic even while dehydrated or internally unwell. Apparent normalcy may not reflect internal changes, especially if signs persist.

My dog stopped vomiting this morning — is it over now?

Not necessarily. Some dogs improve briefly before symptoms return. Temporary improvement does not equal resolution. Watch closely and consider assessment if any sign returns.

Do we really need tests for this?

Yes. Testing helps determine if your dog’s signs are due to infection, inflammation, obstruction, or something more serious. It separates the mild from the dangerous.

What should I do now? Can I wait until tomorrow?

If vomiting and diarrhea have persisted for over 24 hours or your dog is not drinking, eating, or seems tired, do not wait. Urgent evaluation helps stabilize and direct appropriate care.