Many pet owners have experienced the unpleasant surprise of waking up to find their dog has had diarrhea during the night. While it can be alarming, it’s not uncommon for dogs to experience digestive issues, and there are many reasons why this may happen. Some causes of nighttime diarrhea in dogs can be easily remedied with simple changes to their diet or routine, while others may require veterinary attention.

Naturally, if your dog is having nocturnal diarrhea, they may not always make it outside, leading to accidents indoors. So if you’re dealing with this problem, you need to be armed with a dog stain & odor remover to effectively clean up any mess.

Now causes for nighttime diarrhea can differ drastically from dog to dog, sometimes it’s an issue to do with bowel or fecal incontinence, and other times it may be diet, parasites or a medical condition like diabetes. So we’ve consulted the best veterinary and medical sources to look at why a dog may have diarrhea at night.

So, Why Does My Dog Have Diarrhea At Night?

Some possible reasons why your dog may be experiencing diarrhea at night include diabetes, eating something spoiled or rotten, or food they have trouble digesting. Environmental stress in the household at night may also cause diarrhea. Additionally, certain medical conditions, infections, parasites, or inflammatory bowel disease, can cause diarrhea in dogs.

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It is worth noting that some pet parents may only see their dog’s diarrhea at night, when they are home, and not notice that it also happens during the day. In other instances, diarrhea at night can be a sign of a dog becoming incontinent, especially if they are having accidents in the house. This could mean that they have diarrhea at night when their body relaxes (such as when they sleep) and they lose control of their bowel.

Understanding the underlying cause of a dog’s nighttime diarrhea is key to finding the appropriate treatment. But before we look at the different reasons a dog has diarrhea at night, let’s first look at what diarrhea actually is.

Related:

Understanding Diarrhea In Dogs

Let’s break down what could be going on when your dog gets diarrhea, especially at night.

What Is Diarrhea Wrong Really?

First off, not all poop problems are diarrhea. Sometimes, your dog might feel like they urgently need to go and then only pass a small amount, which often That’s different. And, let’s not confuse it with ‘poop accidents,’ okay? Poop accidents at night can happen either because your dog couldn’t get outside to poop at night, or your dog may have fecal or bowel incontinence.

Although diarrhea can make those accidents or incontinence more frequent and messy.

Why is Diarrhea in Dogs a Problem?

Diarrhea can cause some serious issues. Your pup could lose fluids, leaving them dehydrated. They can also lose important stuff like salts and minerals, which can make them weak or even lead to something called “vascular collapse” if it gets really bad. Diarrhea can affect any dog, but it’s usually more dangerous for the very young, the elderly, or those who are already not feeling well for other reasons.

What Causes Canine Diarrhea?

Alright, so your dog’s gut usually soaks up most of the fluid that comes its way, turning it into normal poop. If something messes with that, boom! You’ve got diarrhea. A bunch of things can cause this:

Too much of certain substances: Like when your pup gets into the sugar-free gum or eats people food they shouldn’t. This can mess with how water moves in their intestines.
More fluid and less absorption: This usually happens with infections or food poisoning, but can also occur if they eat something super fatty or are on certain medications.
Fast Transit Time: Sometimes, the poop moves too quickly through the gut, and doesn’t have time to firm up. This can be due to some diseases, surgeries, or even thyroid issues.

Extra Info

Sometimes, medicines or other health issues can cause your dog to poop more quickly, making the problem even worse.
Watch out for green, orange, or yellow stools; this could be a sign that your dog’s gut isn’t absorbing bile salts like it should, which can lead to diarrhea.

11 Causes of Dog Nighttime Diarrhea

1. Food Intolerances & Indiscriminate Eating

Food allergies and intolerances can cause diarrhea in dogs, especially if they consume the offending food at night. Indiscriminate eating problems in dogs, such as eating something rotten or spoiled out of the trash or getting human treats is often the cause.

The reason that food or diet may be causing diarrhea at night has to do with the timing. If you give your dog a cheesy treat when you have dinner at night, and they have a dairy intolerance, they will probably have diarrhea a few hours later. Diarrhea at night may be an adverse food reaction to something your dog may have eaten earlier in the day.

Another very common reason for diarrhea at night is indiscriminate eating in dogs or dogs that are eating out of the garbage. This can be especially true if your dog goes dumpster diving in the evenings and gets your leftovers, upsetting their stomach at night.

Knowing how long it takes a dog to digest food is also important. If your dog eats food they have an allergy and intolerance to, it can cause diarrhea several hours later at night, when their food is digested and causes a reaction. This means that dogs often get diarrhea several hours (and sometimes days) after they eat something they shouldn’t, often causing diarrhea at night.

Symptoms of food allergies and intolerances can vary, but they often include diarrhea, vomiting, flatulence, and stomach pain. In some cases, dogs may also experience skin irritation, itching, and ear infections.

Related:

2. Diabetes

Diabetes is a condition that affects dogs in which their body is unable to properly regulate blood glucose levels. This can lead to a variety of symptoms, including diarrhea at night, losing weight, urinating a lot, drinking water all the time, and seeming hungry all the time.

According to NCBI on GI complications in diabetes, diabetes can cause issues ranging from acid reflux and slowed-down stomach emptying, to problems with the intestines and liver.

Sometimes, dogs with diabetes-related diarrhea might also have diarrhea and accidents — especially at night. Why? Because according to the Cleveland Clinic, diabetes can damage the nerves that control their poop “exit door” (the anal sphincter, if we’re getting technical). When that muscle isn’t working like it should, it can make it hard for your pup to hold it in.

3. Age-Related Muscle Weakness and Canine Cognitive Decline (Doggy Dementia)

As dogs age, they can experience muscle weakness and cognitive decline, which can contribute to diarrhea at night. Age-related muscle weakness can make it difficult for dogs to hold their bowel movements, leading to accidents during the night, especially as they relax while sleeping or if they can’t get outside in time.

Additionally, cognitive decline, or doggy dementia, can cause confusion and disorientation, leading to accidents as well. Anxiety related from cognitive decline can also upset your senior dog’s sleeping patterns and their digestion, making diarrhea at night more likely.

Dogs with cognitive decline may also experience changes in their eating habits and how well their digestive tract functions, which can contribute to diarrhea. This can disrupt the digestive system and lead to diarrhea.

Owners of senior dogs should monitor their pets for signs of muscle weakness and cognitive decline, such as difficulty standing up or walking, confusion, disorientation, and changes in eating habits. If these symptoms are present, owners should consult with their veterinarian to determine the best course of action.

In some cases, medication or dietary changes may be recommended to help manage the symptoms of age-related muscle weakness and cognitive decline. Additionally, providing a comfortable and safe environment for senior dogs can help reduce stress and anxiety, which can exacerbate these symptoms.

4. Certain Medications

Certain medications can cause diarrhea in dogs, especially if they are taken at night. Antibiotics, for example, can disrupt the balance of bacteria in the gut, leading to diarrhea. Other medications that can cause diarrhea include:

Nonsteroidal anti-inflammatory drugs (NSAIDs);
Chemotherapy drugs;
Steroids;
Antacids; and
Antidepressants.

If your dog is taking any of these medications and is experiencing diarrhea at night, it’s important to talk to your veterinarian. They may be able to adjust the dosage or switch to a different medication that is less likely to cause diarrhea.

In some cases, medication-induced diarrhea may be a sign of a more serious underlying condition, such as inflammatory bowel disease or pancreatitis. Your veterinarian can perform diagnostic tests to determine the cause of your dog’s diarrhea and recommend appropriate treatment.

It’s important to note that you should never stop giving your dog medication without first consulting your veterinarian. Abruptly stopping medication can have serious consequences and may make your dog’s condition worse.

5. Inflammatory Bowel Syndrome

Inflammatory Bowel Syndrome (IBS) is a chronic condition that affects dogs, causing inflammation and irritation in the digestive tract. It is a common cause of diarrhea in dogs, especially at night.

The exact cause of IBS is not known, but it is believed to be related to a combination of factors, including genetics, diet, and stress. Dogs with IBS may experience symptoms such as diarrhea, vomiting, abdominal pain, and weight loss.

There is no cure for IBS, but it can be managed with proper treatment and care. Treatment may include changes to the dog’s diet, medication to control inflammation, and stress management techniques.

It is important for dog owners to work closely with their veterinarian to develop a treatment plan that is tailored to their dog’s individual needs. With proper management, dogs with IBS can live happy and healthy lives.

Also see:

Why does my dog poop so much?

6. Internal Parasites

Many studies show that internal parasites like worms and giardia are very common in dogs with diarrhea and gastroenteritis. This diarrhea won’t only happen at night, but sometimes pet parents may only notice their pup’s diarrhea when they are home at night, as the daytime can be busy.

So, Internal parasites are a common cause of diarrhea in dogs, especially in puppies. These parasites can be contracted through contaminated soil or feces, and can cause a range of symptoms including diarrhea, vomiting, and weight loss.

Some of the most common internal parasites that can cause diarrhea in dogs include:

Roundworms: These are the most common internal parasites in dogs. They can be contracted through contaminated soil or feces, and can cause diarrhea, vomiting, and weight loss.
Hookworms: These parasites can be contracted through contaminated soil or feces, and can cause diarrhea, anemia, and weight loss.
Whipworms: These parasites can be contracted through contaminated soil or feces, and can cause diarrhea, weight loss, and anemia.
Giardia: This is a protozoan parasite that can be contracted through contaminated water or feces. It can cause diarrhea, vomiting, and weight loss.

If a dog is suspected of having internal parasites, a veterinarian can perform a fecal examination to determine the type of parasite present and prescribe an appropriate treatment. It is important to follow the veterinarian’s instructions for treatment, as untreated internal parasites can lead to serious health complications.

7. Stress

Stress can be a significant factor in causing diarrhea in dogs, particularly at night. Dogs can experience stress from various sources, such as changes in their environment, separation anxiety, or fear of loud noises. Stress in the home from fighting, stressed, or anxious adults or children, or other disruptions may give your dog a runny tummy at night, when most family members are home from school and work.

Stress can affect the digestive system of dogs by altering the balance of bacteria in their gut, causing inflammation, and increasing the production of digestive acids. These changes can lead to diarrhea, which may occur at night when the dog is resting and the digestive system is less active.

Some signs that a dog may be experiencing stress include panting, pacing, excessive licking, and avoidance behaviors. It is essential to identify the source of stress and address it to prevent further health issues.

Owners can help reduce their dog’s stress levels by providing a calm and stable environment, regular exercise, and positive reinforcement training. In some cases, medication or behavioral therapy may be necessary to manage stress effectively.

It is crucial to consult with a veterinarian if a dog experiences persistent diarrhea, especially if it is accompanied by other symptoms such as vomiting, lethargy, or loss of appetite. A veterinarian can conduct tests to determine the underlying cause of diarrhea and provide appropriate treatment.

8. Spinal & Neurological Disorders

Spinal and neurological disorders can also cause diarrhea in dogs, particularly if they affect the nerves that control the digestive system. Some common examples of such disorders include:

Intervertebral disc disease (IVDD): This condition occurs when the discs between the vertebrae in the spine become herniated or ruptured, causing pressure on the spinal cord. In addition to diarrhea, dogs with IVDD may also experience weakness, pain, and difficulty walking. Research shows that disc herniation often has gastrointestinal symptoms.
Degenerative myelopathy: A progressive disease that affects the spinal cord, degenerative myelopathy can cause a range of symptoms, including diarrhea, incontinence, and hind limb weakness.
Epilepsy: While epilepsy is primarily a neurological disorder that causes seizures, it can also affect the digestive system and cause diarrhea as a secondary symptom.

It’s important to note that spinal and neurological disorders are relatively rare causes of diarrhea in dogs. However, if a dog is experiencing other symptoms in addition to diarrhea, such as weakness or difficulty walking, it’s important to seek veterinary attention right away.

9. Colitis

Colitis is a condition that causes inflammation in the colon, leading to diarrhea. There are several types of colitis, but the most common type in dogs is idiopathic colitis, which means that the cause is unknown. However, it is believed that stress, diet, and bacterial infections may play a role in the development of this condition.

Symptoms of colitis in dogs include diarrhea, which may be bloody or mucousy, straining to defecate, and increased frequency of bowel movements. Dogs with colitis may also have a decreased appetite, lethargy, and weight loss.

Treatment for colitis typically involves a combination of dietary changes and medication. A low-residue diet, which is low in fiber, is often recommended to reduce the workload on the colon. Probiotics may also be prescribed to restore the balance of bacteria in the gut. In more severe cases, anti-inflammatory drugs or antibiotics may be necessary.

It is important to note that colitis can be a chronic condition, and some dogs may require ongoing treatment to manage their symptoms. Regular check-ups with a veterinarian are recommended to monitor the dog’s condition and adjust treatment as necessary.

10. Infectious Disease (Viral, Fungal, or Bacterial)

Diarrhea in dogs can also be caused by infectious agents such as viruses, bacteria, and fungi. These agents can be transmitted by contact with infected animals, contaminated food, or water. In some cases, they can also be transmitted by insects such as fleas and ticks.

One of the most common viral infections that can cause diarrhea in dogs is parvovirus. This virus is highly contagious and can be spread through contact with infected feces or vomit. Dogs that are not vaccinated or have a weakened immune system are more susceptible to this virus. Symptoms of parvovirus include vomiting, diarrhea, lethargy, and loss of appetite.

Bacterial infections such as salmonella, campylobacter, and E. coli can also cause diarrhea in dogs. These bacteria can be found in contaminated food or water, and can also be transmitted by contact with infected animals. Symptoms of bacterial infections include diarrhea, vomiting, fever, and abdominal pain.

Fungal infections such as histoplasmosis and blastomycosis can also cause diarrhea in dogs. These infections are caused by inhaling fungal spores found in soil, bird droppings, and other organic matter. Symptoms of fungal infections include diarrhea, weight loss, and lethargy.

Infectious diarrhea can be diagnosed by a veterinarian through a fecal examination and blood tests. Treatment for infectious diarrhea may include antibiotics, antifungal medication, and supportive care such as fluid therapy and nutritional support. It is important to keep infected dogs isolated from other animals to prevent the spread of the infection.

11. Organ Failure

In some cases, diarrhea in dogs at night can be caused by organ failure. When the organs in a dog’s body are not functioning properly, they can lead to various symptoms, including diarrhea.

The liver and kidneys are two of the most important organs in a dog’s body. If they are not working correctly, it can lead to diarrhea (but diarrhea at night is also common with dogs with congestive heart failure). The liver is responsible for filtering toxins from the blood, while the kidneys are responsible for filtering waste products from the blood. If these organs are not functioning properly, toxins and waste products can build up in the body, leading to diarrhea.

Other symptoms of organ failure in dogs may include:

Loss of appetite;
Vomiting;
Lethargy;
Weight loss; and
Increased thirst and urination.

If a dog is experiencing these symptoms, it is important to take them to a veterinarian for a proper diagnosis and treatment. Treatment may involve medication, dietary changes, and in severe cases, hospitalization.

It is important to note that organ failure is not a common cause of diarrhea in dogs at night. However, if a dog is experiencing other symptoms in addition to diarrhea, it is important to rule out organ failure as a potential cause.

Understanding Secretory Diarrhea In Dogs

Research on diarrhea in dogs points to something called secretory diarrhea. Secretory diarrhea occurs when the intestinal cells secrete excess fluid into the bowel lumen, which results in watery diarrhea. The fluid secretion may be due to the presence of toxins, viruses, or bacteria that stimulate the cells to secrete fluid.

The most common causes of secretory diarrhea are viral gastroenteritis, bacterial infections, and food poisoning. In dogs, viral gastroenteritis caused by parvovirus is a common cause of secretory diarrhea. The virus invades the intestinal cells, causing them to secrete fluid and leading to watery diarrhea.

If your dog has gastroenteritis, it can also involve vomiting, even vomiting blood. So be sure to read our article on when to feed dogs after throwing up.

Other factors that can cause secretory diarrhea in dogs include stress, dietary changes, and medication side effects. Stress can cause an increase in the production of hormones that stimulate intestinal fluid secretion. Dietary changes can also cause diarrhea, as the dog’s digestive system may not be able to handle certain foods. Medications such as antibiotics can disrupt the balance of normal gut bacteria, leading to diarrhea.

Treatment for secretory diarrhea involves addressing the underlying cause. In cases of viral gastroenteritis, supportive care such as fluid therapy and anti-nausea medications may be necessary. In cases of bacterial infections, antibiotics may be required. In cases of stress-related diarrhea, reducing stressors and providing a calm environment can help alleviate symptoms.

Overall, secretory diarrhea can be a serious condition that requires prompt veterinary attention. If your dog is experiencing persistent diarrhea, it is important to seek veterinary care to determine the underlying cause and appropriate treatment.

Preventive Measures For Dogs With Nighttime Diarrhea

Proper Diet

Feeding your dog a well-balanced diet with high-quality ingredients can help prevent digestive issues. Avoid feeding your dog table scraps or foods that are high in fat or sugar.

Hydration

Make sure your dog has access to clean, fresh water at all times. Dehydration can cause digestive issues and make diarrhea worse.

Exercise

Regular exercise can help keep your dog’s digestive system healthy. Make sure your dog gets plenty of exercise every day.

Stress Management

Stress can cause digestive issues in dogs. Try to keep your dog’s environment calm and stress-free.

Regular Vet Check-Ups

Regular check-ups with your veterinarian can help identify and treat health issues before they become more serious.

By following these preventive measures, you can help keep your dog healthy and prevent diarrhea at night.

When to Consult a Vet

If a dog has diarrhea at night, it can be a sign of a more serious underlying condition. Therefore, it is important to know when to consult a vet. Here are some signs that indicate it is time to seek veterinary care:

Diarrhea that lasts for more than two days;
Diarrhea that is accompanied by vomiting;
Diarrhea that is bloody or black in color;
Loss of appetite;
Lethargy or weakness; and
Dehydration.

If a dog exhibits any of these symptoms, it is important to take them to a vet as soon as possible. The vet will perform a physical examination and may recommend further tests such as blood work or fecal analysis. Depending on the underlying cause of the diarrhea, the vet may prescribe medication or recommend dietary changes.

It is important to note that some dogs may be more prone to diarrhea than others. For example, dogs that have a sensitive stomach or are prone to anxiety may experience diarrhea more frequently. In these cases, it is still important to consult a vet if the diarrhea persists or is accompanied by other symptoms.

Overall, if a dog has diarrhea at night, it is important to monitor their symptoms and seek veterinary care if necessary.

Frequently Asked Questions (FAQs)

What are common causes of nighttime diarrhea in dogs?

There are many potential causes of nighttime diarrhea in dogs. Some common causes include dietary indiscretion, stress, diabetes, parasites, infections, and food allergies or intolerances. It’s important to identify the underlying cause of your dog’s diarrhea in order to effectively treat it.

How can I treat my dog’s diarrhea at night?

Treatment for nighttime diarrhea in dogs will depend on the underlying cause. In some cases, simple dietary changes or medication may be enough to resolve the issue. However, if your dog’s diarrhea is severe or persistent, it’s important to seek veterinary care.

Is it normal for dogs to have diarrhea at night?

While occasional bouts of diarrhea are not uncommon in dogs, it is not normal for a dog to have diarrhea on a regular basis. If your dog is experiencing frequent or persistent diarrhea, it’s important to seek veterinary care to identify and address the underlying cause.

When should I take my dog to the vet for nighttime diarrhea?

If your dog is experiencing severe or persistent diarrhea, or if they are showing other signs of illness such as vomiting, lethargy, or loss of appetite, it’s important to seek veterinary care as soon as possible. Additionally, if your dog is a young puppy, elderly, or has an underlying health condition, it’s important to seek veterinary care promptly.

What can I do to prevent my dog from getting diarrhea at night?

There are several steps you can take to help prevent your dog from experiencing nighttime diarrhea. These include feeding your dog a high-quality diet, providing plenty of fresh water, avoiding table scraps and other human foods, and keeping your dog’s environment clean and stress-free. It’s also essential to check your dog for medical issues like diabetes.

Can feeding my dog after a night of diarrhea make it worse?

Feeding your dog after a night of diarrhea can potentially make the diarrhea worse, especially if the underlying cause is related to diet or food allergies. However, withholding food for too long can also be detrimental to your dog’s health. It’s important to work with your veterinarian to develop an appropriate feeding plan based on your dog’s individual needs and health status.

Conclusion

In conclusion, there are several reasons why a dog may experience diarrhea at night. These can range from dietary changes to underlying medical conditions. It is important for pet owners to stay vigilant and monitor their dog’s behavior and health closely.

If a dog experiences diarrhea for more than a day or two, it is recommended to seek veterinary care. The veterinarian can perform diagnostic tests to determine the underlying cause of the diarrhea and provide appropriate treatment.

Pet owners can take preventative measures to reduce the likelihood of their dog experiencing diarrhea at night. This includes maintaining a consistent diet, avoiding table scraps and human food, and providing plenty of water.

Overall, while diarrhea at night can be concerning for pet owners, it is often treatable and manageable with proper care and attention. By staying informed and proactive, pet owners can help their furry friends stay healthy and happy.

Meet Your Experts

Tamsin De La Harpe

Author

Tamsin de la Harpe has nearly two decades of experience with dogs in rescue, training, and behavior modification with fearful and aggressive dogs. She has worked closely with veterinarians and various kennels, building up extensive medical knowledge and an understanding of canine health and physiology. She also spent two years in the animal sciences as a canine nutrition researcher, focusing on longevity and holistic healthcare for our four-legged companions. Tamsin currently keeps a busy homestead with an assortment of rescue dogs and three Bullmastiffs.