If your dog is eating grass and not eating and vomiting, it may seem like a confusing mix of symptoms.
While grass-eating behavior is often seen in dogs, when it’s accompanied by loss of appetite and vomiting, it could point to an underlying issue that requires attention.
These signs may seem unrelated at first, but when they appear together, they could be your dog’s way of signaling distress.
Understanding why this happens, the potential causes, and what actions to take is essential for your dog’s well-being.
Dog Eating Grass and Not Eating and Vomiting: Why It Happens
When a dog is eating grass and not eating and vomiting, it’s often a sign of underlying gastrointestinal discomfort or distress.
This combination of symptoms can result from several potential causes including gastrointestinal upset, pancreatitis, toxin ingestion, intestinal parasites, obstruction, inflammatory bowel disease (IBD), stress or anxiety, and poor diet.
While grass-eating alone may not be alarming, its occurrence alongside vomiting and refusal to eat suggests the dog is trying to self-soothe or eliminate something irritating their digestive system.
Dog Eating Grass and Not Eating and Vomiting: Common Causes
Gastrointestinal upset
The most common reason a dog is eating grass and not eating and vomiting is gastrointestinal distress.
Grass may irritate the stomach lining, triggering vomiting, or the dog may already feel nauseated and use grass as a natural emetic.
Gastrointestinal upset can result from dietary indiscretion—eating something they shouldn’t have—food allergies, spoiled food, or abrupt changes in their diet.
The body responds with vomiting and refusal to eat until the irritation subsides.
Pancreatitis
Pancreatitis in dogs is an inflammation of the pancreas, often triggered by fatty food or an underlying metabolic condition.
If your dog is eating grass and not eating and vomiting, pancreatitis could be the reason.
Other signs may include a hunched posture, abdominal pain, diarrhea, and lethargy.
Dogs with pancreatitis may attempt to relieve nausea by eating grass, but it only worsens their vomiting and discomfort.
Related: Dog eating grass and not eating (Here’s why)
Toxin ingestion
When a dog eats something toxic—like human medications, certain plants, pesticides, or household chemicals—the body may respond with vomiting and loss of appetite.
In some cases, the dog may instinctively eat grass in an attempt to clear the toxin from its system.
If your dog is eating grass and not eating and vomiting, and you suspect they may have ingested a harmful substance, seek emergency veterinary care.
Some toxins can damage the liver, kidneys, or gastrointestinal tract rapidly.
Intestinal parasites
Parasites such as roundworms, hookworms, or giardia can upset the digestive system.
A dog with parasites may show symptoms like eating grass, vomiting, diarrhea, and weight loss.
Infections can lead to discomfort or nausea, prompting the dog to stop eating and try to self-medicate with grass.
Obstruction or foreign object ingestion
Dogs that eat non-food items—like socks, plastic, bones, or toys—may develop a gastrointestinal obstruction.
This can prevent food and fluids from moving properly through the digestive tract.
If a dog is eating grass and not eating and vomiting repeatedly, and their abdomen appears bloated or tender, a blockage could be the cause. This is a medical emergency.
Inflammatory bowel disease (IBD)
Inflammatory bowel disease can affect how the body absorbs nutrients and can lead to chronic vomiting, diarrhea, and loss of appetite.
Dogs with IBD may eat grass out of discomfort or nausea.
If your dog has a history of GI issues, this could be an underlying factor.
Stress or anxiety
Stress and anxiety can have a direct impact on your dog’s digestive system.
A stressed dog may eat grass more frequently as a coping mechanism, and the same stress can reduce appetite and cause vomiting.
Changes in routine, new environments, loud noises, or separation anxiety can all contribute.
Dietary imbalance or poor nutrition
Dogs that aren’t receiving adequate fiber or essential nutrients in their diet may resort to grass-eating behavior.
If your dog is eating grass and not eating and vomiting, poor nutrition could be contributing to the behavior.
Some commercial dog foods may lack the proper balance for certain breeds or sizes.
Related: Dog Eating Grass and Not Eating and Diarrhea (Causes and what to do)
When to worry: Signs that require immediate attention
If your dog is eating grass and not eating and vomiting more than once in a 24-hour period, or if additional symptoms appear, it’s time to see a vet.
Here are red flags that indicate urgent care is needed:
Repeated or projectile vomiting
Vomit containing blood or bile
Severe lethargy or weakness
Abdominal swelling or tenderness
Persistent refusal to eat or drink
Diarrhea along with vomiting
Suspected poisoning or ingestion of foreign objects
High fever or signs of pain
These signs may point to serious conditions that require prompt diagnosis and treatment.
Delaying veterinary care can lead to complications, especially in puppies, senior dogs, or those with existing health issues.
What to do
Here are steps to take if you notice your dog displaying these concerning symptoms:
1. Remove access to grass and unfamiliar objects
Prevent further grass-eating to avoid additional vomiting or irritation.
Also remove access to potential toxins, garbage, or chewable non-food items.
2. Monitor symptoms closely
Take note of how often your dog is vomiting, whether there’s blood in the vomit, or if other symptoms arise such as diarrhea, pacing, or panting.
Keep track of their water intake and urination.
3. Offer bland food after a period of fasting
If your dog has only vomited once or twice and seems stable, you can withhold food for 8–12 hours, then offer a bland diet like boiled chicken and plain rice.
Avoid fatty foods, treats, or rich kibble during this time.
4. Encourage hydration
Vomiting and reduced appetite can lead to dehydration. Offer fresh water frequently.
You can also offer unseasoned bone broth or ice cubes to entice your dog to hydrate.
5. Seek veterinary care
If vomiting continues, or if your dog is not eating for more than 24 hours, contact your veterinarian.
Diagnostic tests such as x-rays, bloodwork, or fecal analysis may be needed to identify the root cause.
6. Follow vet-recommended treatment
Depending on the diagnosis, your vet may prescribe anti-nausea medication, fluid therapy, parasite treatment, or a special gastrointestinal diet.
In serious cases like obstruction or pancreatitis, hospitalization or surgery may be necessary.
Preventing future episodes
To reduce the chances of your dog eating grass and not eating and vomiting in the future, take these preventative steps:
Ensure your dog has a balanced, high-quality diet suited to their breed and age
Keep harmful substances, trash, and small chewable items out of reach
Provide regular deworming and parasite control
Reduce stress by maintaining a consistent routine and using calming strategies if needed
Provide appropriate chewing alternatives and stimulation to avoid boredom-related grass-eating
Monitor their outdoor activity to limit unsupervised grazing
Key Takeaway
A dog eating grass and not eating and vomiting isn’t something to ignore, especially if the symptoms persist or worsen.
While some grass-eating behavior is normal, it becomes a concern when accompanied by appetite loss and vomiting.
These signs may point to gastrointestinal issues, pancreatitis, toxin ingestion, or even intestinal blockage.
Understanding why your dog might be eating grass and not eating and vomiting can help you identify potential problems early.
With timely care, a proper diet, and preventative measures, you can help your dog stay happy, healthy, and symptom-free.
If in doubt, always consult your veterinarian to rule out serious conditions.