Can separation anxiety cause vomiting & diarrhea in dogs?

Separation anxiety is very stressful for dogs, and like in humans, stress can cause stomach upsets. This means it’s definitely possible for separation anxiety to cause vomiting or diarrhea in dogs.

However, it’s important to be sure that your dog is suffering from separation anxiety, just in case their symptoms are being caused by something more serious.

Let’s explore what separation anxiety looks like in dogs, how to fix it, and what else it could be if it’s not separation anxiety.  

Table of Contents

dog with separation anxiety ruined the chair

What is separation anxiety? 

Separation anxiety is when dogs feel distressed at being apart from their owners or families. It is thought to affect around 14% of dogs in the United States and is more likely to occur in puppies, rescue dogs, intelligent breeds, older dogs, and dogs experiencing a frightening illness or recovering from a traumatic event or abuse. 

More often than not, it’s caused by a lack of confidence and independence. Under-stimulation often plays a part, as well. This is because stress is energy, so the more exercise and enrichment your dog gets, the less room they have in their lives for stress

What are the symptoms of separation anxiety?

To be absolutely sure that your dog’s vomiting and diarrhea are caused by separation anxiety, you need to consider whether or not they are displaying other signs of anxiety. Other signs include repetitive behaviors such as pacing, shaking, and drooling.

Separation anxiety can also cause destruction towards their own possessions and household items. Many dogs with separation anxiety also bark and whine excessively whenever their owners leave the house, go to the toilet indoors, or try to get out of the house. They may even hurt themselves through excessive scratching, biting, and licking. 

How to react to separation anxiety symptoms

If your puppy is destructive when you leave the house, don’t react angrily. This could increase their anxiety and make their symptoms worse. It could even encourage their behavior because they are desperate for your attention, and don’t forget, it’s not their fault. 

You should never punish a dog with separation anxiety. Instead, you should show them that this kind of behavior doesn’t get any attention, but when they do behave well, shower them with praise. To stop separation anxiety behaviors altogether, you will need to do some separation training. 

vomiting & diarrhea

How to do separation training 

In order to prevent or put a stop to separation anxiety and all of its symptoms, you need to create a sense of independence in your dog. 

You can do this by gradually introducing time apart. First, try leaving the house for a matter of minutes. Don’t make a big thing about leaving, as this can encourage feelings of anxiety, but always say goodbye so that they know what’s happening. Instead, you should make a big deal when you return, as this reinforces that there is something to look forward to when you go out. 

The next day, leave the house for slightly longer and continue to do so, adding on a little more time each day. This creates a reassurance in your dog that whenever you leave, you will always return. If you do this most days, you should see a significant difference in your dog’s symptoms within weeks. 

To build confidence in your dog, you should try to make positive associations with spending time alone, too. Encourage your dog to play by themselves using a puzzle toy or treat dispenser when you’re at home.

Then, next time you go out, give it to them just before you go out and leave them with it. This will give your dog something fun to do in your absence and teach them that time alone can be fun and rewarding. 

It’s also wise to desensitize your dog to indicators of separation. Try doing things that you would normally do before going out, such as putting your shoes on. Then, instead of leaving the house, carry on whatever you were doing. This will teach your dog that your actions are nothing to worry about and should relieve some anticipatory anxiety. 

Reducing anxiety in dogs

If your dog’s separation anxiety is extreme, try out an anti-anxiety supplement or plug-in diffuser to aid your training. They are completely natural and harmless and are known to effectively reduce stress in pets. 

As mentioned above, under-stimulation can contribute to separation anxiety. So, to reduce anxiety, make sure your dog is receiving enough exercise and having lots of fun and social interactions.

How much exercise your dog needs depends on their age, size, and breed, so ask your vet for exact advice. You should try to go to different places, do different activities, and interact with lots of people and dogs to make your walks as stimulating as possible. 

Socializing is great for dogs with separation anxiety. It helps them to feel fulfilled and eliminates loneliness. Try to include your dog in your life as much as possible, give them lots of love, and never leave them alone for more than four hours at a time.  

Play and mental stimulation are arguably the best ways to reduce anxiety. Games like hide and seek and treasure hunt are perfect stress-busters for dogs, and toys such as puzzle games, feeding mats, and treat dispensing balls are ideal for anxious minds. 

Alternative causes of vomiting & diarrhea in dogs

If you don’t think your dog’s stomach upsets are being caused by separation anxiety, it’s a good idea to familiarise yourself with what else it could be. Like in humans, there are numerous possible causes of stomach upsets in dogs, but some are more likely than others. 

The most common non-illness-related causes of vomiting and diarrhea in dogs include internal blockages, ingesting something poisonous, food allergies, dietary changes, medications, and other forms of stress or anxiety. Health conditions that commonly cause stomach upsets include viruses, infections, gastroenteritis, pancreatitis, parasite infestations, and chronic conditions like inflammatory bowel disease and cancer. 

Internal blockages

Dogs can get internal blockages from swallowing indigestible, non-food objects. Common culprits are toys, rocks, and sticks. As well as stomach upsets, internal blockages or obstructions can cause bloating, abdominal pain, hunching over, and a loss of appetite. 

If you suspect your dog of having an internal blockage, you should call your vet immediately. They may be able to tell where the blockage is from feeling your dog’s stomach, and they may also perform an x-ray to see exactly what the blockage is. Depending on what and where it is, your vet may be able to induce vomiting to remove the blockage, or they may have to operate. With quick treatment, most dogs should make a full recovery. 

Ingesting toxins 

When a dog ingests a toxic substance, such as a food item, plant, or pesticide, it can cause vomiting and diarrhea, as well as excessive drooling, and in severe cases, shaking, seizuring, drunk walking, and unconsciousness or coma. Other symptoms can occur depending on what was ingested, but these are the generic signs of poisoning. 

If you are worried about something you dog has ingested, you should call your vet for advice. If it’s out of hours, call the Pet Poison Helpline instead. Depending on what was ingested, they may tell you to wait and see or go to the nearest emergency vet hospital. 

If what your dog ingested is life-threatening, such as antifreeze, vets may be able to give your dog an antidote, but this only works if you act quickly. Less serious cases of poisoning may require induced vomiting or rehydration to accommodate the natural purging of the toxin.

Food allergies

Dogs can experience food intolerances and allergies just like humans can. They can cause vomiting, diarrhea, gas, and stomach aches. Allergies can also cause dermatologic symptoms such as itchiness, poor skin and coat health, and chronic ear infections.  

Common food allergies in dogs include grains like gluten, soy, and certain proteins, especially those found in dairy products, eggs, and chicken, beef, and lamb. If you suspect your dog of having a food allergy, talk to your vet about doing a food trial. This is a special eliminatory diet that gradually works out what is causing your dog’s allergies, and it usually takes between 6-12 weeks to do.

Once you know the issue, you can cut out the allergen. There are tonnes of commercial kibbles these days that are free from grains and common allergens. If your dog’s allergy is something more complex, like protein, you may have to do some trial and error to see what works, but salmon is usually a good choice.

funny dog at the table eating

Dietary changes

If your dog has a sensitive stomach, a change in diet can cause temporary a stomach upset. This doesn’t necessarily mean that your dog is allergic to whatever change you are introducing, it just means that their digestive system needs time to adjust. 

This is likely the case if you are making a significant transformation, for example, going from commercial food to a raw diet. When drastically changing your dog’s diet, you should do it gradually. 

For example, fill ¾ of their bowl with their old food and ¼ with the new food for the first 2-3 days, and then make it half and half. If their body reacts well, wait a day or two and make it ¾ new food. Then, after a day or two, make it 100% new food. If at any point their stomach starts reacting badly, go back a step and wait a couple of days.


Certain medications can also cause stomach upsets in dogs. Like human medication, pet medication can come with side effects. This can happen with several medications including anti-parasitic medications and antibiotics. To offset this, you should make sure your dog keeps hydrated and eats lots of nutritious food. If you are worried that your dog is allergic to the medication, speak to your vet about alternative medicines. 

Stress & anxiety

It’s also possible that your dog could be experiencing some other form of anxiety or stress. Common causes of stress and anxiety besides separation anxiety include big life changes or changes in schedule, trauma, phobias, illness, and illness or death in the family. 

The signs are much the same as separation anxiety but are likely to occur throughout the day or night rather than just when you’re apart. If your dog is experiencing stress or anxiety, you should try to associate their triggers with something positive if possible, or avoid them altogether. 

Providing a stable daily routine with lots of love, long walks, and mentally stimulating play will also help. Invest in some anti-anxiety products if your dog’s stress is severe, and don’t be afraid to consult a trainer or behaviorist if you’re struggling. 


There are several viruses that can cause vomiting and diarrhea in dogs. The most common being canine parvovirus. However, they are almost all things that dogs are vaccinated against in their first weeks of life, so they’re more likely to occur in puppies and stray or rescue dogs

When questioning the origin of your dog’s upset stomach, consider their background and contact your vet if you think they could have a virus. Vets can test for most viruses via blood testing and treat them with medication and vaccinations. It’s essential to get dogs treated and vaccinated, as viruses such as canine parvovirus are highly contagious and have extremely high mortality rates when left untreated. 


Dogs can get both fungal and bacterial infections, both in the skin and internally. They are typically picked up by coming into contact with, inhaling, or ingesting contaminants, and they can quickly spread around the body. 

External infections are easy to identify; an area of the skin will be cut or wounded, red, and causing irritation. It may also have spots, pus, or discharge, accompanied by an unpleasant smell. This could be on the skin, in the eyes, or inside the ears. 

Internal infections, especially those affecting the stomach or intestines, almost always cause vomiting and diarrhea and are often accompanied by a fever and/or chills, low energy, a lack of appetite, pain or discomfort, and accelerated breathing. 

It’s essential to get infected dog treatment, or the infection could spread and become septic. Once a vet has run tests, they will prescribe antibiotics or antifungal medications to clear up the infection.


Gastroenteritis is defined by inflammation of the stomach and/or intestines. It usually causes vomiting and diarrhea, as well as pain in the stomach and loss of appetite. In severe cases, there may be blood in the vomit or diarrhea. 

The exact causes are mostly unknown but are thought to relate to eating unusual or spoiled food, toxins, bacteria, and can be linked to underlying health problems, too, such as liver and kidney disease.

When severe, gastroenteritis can kill pets, so it’s important to take your dog to their vet as soon as possible. Your vet will ask you about their symptoms, do an examination, and possibly run a few tests to diagnose the condition. 

Treatment will vary depending on the severity of your dog’s condition, but more often than not, gastroenteritis is treated with a temporarily bland diet, medication, and electrolytes for rehydration. Severe cases may require IV-fluid treatment, but the majority of cases will clear up within a few days to a week. 


Pancreatitis usually occurs when a dog consumes too much fat, either once or over time. It can be very painful and serious if left untreated. Symptoms include vomiting and diarrhea, stomach pain, and a loss of appetite. Vets may test blood as well as run X-rays and ultrasounds to diagnose the condition. 

Mild pancreatitis can be treated with rest, pain killers, anti-inflammatory medicines, dietary changes, and rehydration treatments. The prognosis with treatment is generally pretty good. However, dogs with severe cases may need to be hospitalized for IV-fluid treatment and stronger medications. 


Dogs can easily pick up parasites outdoors through their mouths and noses. They can even enter the skin and be passed on by other animals, through fleas, and newborn pups can also get them from their mothers at birth.

Parasites are insects that live and feed in or on another animal, and common parasites that affect dogs are fleas and worms. If unprotected or left untreated, parasites can invade and attack everything in the body, causing serious illness and even death. 

To protect against parasites, owners should give their dogs preventative medications on a regular basis. If you do give your dog protective medications, parasites shouldn’t be the cause of your dog’s stomach upsets. 

Stomach upsets are one of the main symptoms of an internal parasitic infestation, and it’s often accompanied by a swollen stomach, weight loss, dehydration, and lethargy. It’s usually tested for through fecal tests. Thankfully, they’re easily treated with oral anti-parasitic medications that can be bought over the counter or on prescription. 

Inflammatory Bowel Disease

Inflammatory bowel disease (IBD) is a condition in which a dog’s digestive system or intestine becomes chronically inflamed. There is no known sole cause but factors are thought to include genetics and weak immune systems. 

The continued inflammation can cause damage to the lining of the digestive tract in a way that prevents proper digestion. The most common symptoms are vomiting, diarrhea, lethargy, changes in appetite, and weight loss.

Although there is no cure, it’s very manageable through prescription medications and changes in diet. Initial testing includes fecal examinations, blood testing, and X-rays or ultrasounds of the stomach or intestines. A surgical biopsy can also be performed to determine the exact type of IBD. So long as the condition is managed, it shouldn’t affect a dog’s length or quality of life


Cancer is a common cause of death in dogs, and several types of cancer can cause vomiting and diarrhea, most commonly stomach cancer. This is more likely when stomach upsets are frequent and recurring in older pets. If you cannot find a more obvious cause of their stomach upsets, talk to your vet about testing for cancer. 

What to do when your dog has an upset stomach

When your dog has an upset stomach, don’t panic. Reassure them and clean them up afterward if necessary. If your dog guards their vomit, call them into another room and keep them separate from it whilst you clean it up. If your vet has asked you to get a sample, use a sterilized container and place the lid on top of it securely as soon as you’ve taken the sample. 

Should you stop feeding a dog with an upset stomach?

Until you find out what is causing your dog’s upset stomach, keep their diet bland and simple but don’t stop feeding them – unless a vet has told you to do so. 

Their bodies will likely need the nutrients to fight off what is causing the symptoms and help them to recover, so be sure to give them plain, healthy food. 

upset dog laying inside

Vets usually recommend rice and chicken. Pumpkin is also good for upset stomachs, as it is high in fiber to regulate digestion and contains tonnes of great vitamins and minerals for the whole body, including vitamins A, B6, C, E, manganese, copper, riboflavin, potassium, thiamin, niacin, v folate, iron, and phosphorus. Just make sure it’s cooked, peeled, plain, and unseasoned. 

How to help your dog recover from vomiting and diarrhea

If your dog has been suffering from vomiting and diarrhea, they are likely to be significantly dehydrated. 

Once you have identified the underlying issue and have come up with a treatment plan with your vet, you should try to rehydrate your dog with water and electrolytes. Electrolytes contain key minerals that help the body to do a lot of its work and aid recovery, and you can usually buy oral electrolyte solutions online or at the vets. 

If your dog is recovering from a food-related issue, gastrointestinal issue, or something that required strong medication, your vet may also advise you to give your dog a bland diet to aid their recovery and probiotics to rebalance their gut bacteria.

The bottom line

Although separation anxiety can cause stomach upsets, it’s important to be sure that it is the cause. Watch out for other symptoms and behaviors, and if you’re concerned about your dog’s health, make an appointment with your vet right away.

Laura <br> <h6>Writer and Border Collie Mom​</h6>


Writer and Border Collie Mom​

Laura is a dog-lover with an animal-related degree and plenty of hands on experience. She is passionate about dog health & welfare and wants to arm owners with all of the essential info they need!