Why Does My Dog Get Diarrhea?

Why Does My Dog Get Diarrhea When Boarding?

One of the most common questions we hear after a boarding stay or frequent daycare is:

"My dog had diarrhea while they were there. Why?"

The short answer? Sometimes, life is exciting.

Veterinarians even have a nickname for it: stress colitis. While it sounds alarming, it is a very common and often temporary condition that can occur when a dog's normal routine is disrupted.

What Happens During Boarding?

Imagine spending several days at a resort where:

• New people are everywhere
• New sounds never seem to stop
• New smells are around every corner
• Your daily schedule changes
• You're sleeping somewhere unfamiliar
• Your family disappears for a few days

Even when dogs are having a wonderful time, their bodies recognize that things are different.

Many dogs experience:

• Less sleep than they get at home
• Increased excitement and stimulation
• More activity and exercise
• Changes in eating habits
• Mild stress or anxiety
• Increased cortisol (stress hormone) levels

Some dogs become so interested in everything happening around them that they eat less than normal. Others play harder than they do at home. Some simply have trouble settling into a new routine. Any combination of these factors can affect the digestive system.

What Is Stress Colitis?

The large intestine, or colon, is particularly sensitive to stress.

When dogs become excited, anxious, overstimulated, overtired, or experience a major change in routine, inflammation can occur in the colon. This often results in:

• Soft stool
• Mucus-covered stool
• Increased urgency
• More frequent bowel movements
• Diarrhea

Many otherwise healthy dogs experience mild stress colitis during boarding, travel, competitions, hunting trips, veterinary hospitalization, or even family gatherings.

It's Not Always Stress

Of course, not every case of diarrhea is stress-related.

That's why we monitor every pet carefully and look for signs that suggest something more serious may be occurring.

Red flags include:

• Repeated vomiting
• Refusal to drink water
• Lethargy or weakness
• Blood in stool
• Black, tarry stool
• Fever
• Severe dehydration
• Symptoms that worsen instead of improve

These signs warrant closer evaluation and may require veterinary attention.

What About Vomiting?

Vomiting can occur for many of the same reasons.

Dogs experiencing excitement, anxiety, disrupted routines, vigorous activity, or skipped meals may occasionally vomit.

In some cases, dogs become so interested in their surroundings that they simply don't eat as they normally would. An empty stomach can lead to bile vomiting, often appearing as yellow or foamy liquid.

As with diarrhea, occasional vomiting may not be unusual, but repeated vomiting or signs of illness should always be taken seriously.

What About Water Vomiting?

Another occasional occurrence in active dogs is what many veterinarians and kennel professionals informally refer to as "water vomiting."

After a vigorous play session, some dogs become extremely thirsty and drink large amounts of water very quickly. Occasionally, that water comes right back up moments later.

While it can be surprising to witness—especially when it seems like an impossible amount of water—it is often simply the result of drinking too much, too fast after activity or excitement.

The resulting vomit is typically:

• Mostly clear water
• A single episode
• Not accompanied by other signs of illness
• Followed by a dog who immediately returns to normal activities

This differs from repeated vomiting, vomiting associated with illness, or vomiting accompanied by lethargy, loss of appetite, abdominal discomfort, or other concerning symptoms.

As with all digestive issues, we monitor these episodes carefully. While occasional water vomiting after play is not uncommon, repeated vomiting or other signs of illness warrant closer attention.

Daycare Dogs Can Experience It Too

Boarding isn't the only trigger.

Daycare dogs occasionally develop loose stools after particularly active days. Increased exercise, excitement, play, stimulation, and changes in hydration can all affect the digestive tract.

Think of it as the canine equivalent of overdoing it at an amusement park, a marathon, or an all-day sporting event.

What Can Owners Do?

If your pet is prone to digestive upset during travel or boarding, talk with your veterinarian before your stay.

Some strategies veterinarians commonly recommend include:

• Maintaining a consistent diet before and after boarding
• Sending your pet's regular food from home
• Avoiding sudden food changes
• Using veterinarian-approved probiotics
• Ensuring adequate hydration
• Discussing stress-management options for particularly anxious pets

Cats Experience It Too

While cats generally express stress differently than dogs, they are not immune to digestive upset.

Changes in routine, unfamiliar surroundings, travel, new smells, and separation from their family can all contribute to:

• Reduced appetite
• Vomiting
• Soft stool
• Diarrhea

Cats often hide signs of stress more effectively than dogs, which makes careful monitoring especially important.

The Bottom Line

Most episodes of mild diarrhea during boarding are not caused by illness, poor food, or inadequate care. More often, they are the digestive system's response to excitement, stimulation, disrupted routines, and the many changes that come with being away from home.

Even in the most comfortable environment, boarding is still an adventure—and sometimes the digestive system joins in.

As always, our team monitors eating habits, hydration, stool quality, activity levels, and overall wellness throughout every stay. If something falls outside what we'd expect from normal boarding-related stress, excitement, or activity, we'll let you know.