It’s not unusual to see your dog eating grass during a walk or in the backyard—but when that behavior is followed by gagging, it can quickly become a cause for concern.
While occasional grass-eating is considered normal canine behavior, gagging immediately afterward could indicate something more serious.
We outline what it means when a dog eats grass and starts gagging, the causes behind this behavior, and what you should do about it.
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Here’s Why Dogs Eat Grass But Not Food
When a dog is eating grass and gagging, it’s usually a sign of gastrointestinal discomfort or irritation. This behavior might be your dog’s way of trying to induce vomiting or relieve an upset stomach. Gagging often follows grass-eating when the grass tickles the throat or stomach lining, which can trigger the reflex to vomit.
What Does Eating Grass But Not Food Mean?
Below are the common reasons for this behavior:
1. Digestive Upset or Nausea
One of the most common reasons dogs eat grass but not food is because they feel nauseous or have an upset stomach.
Grass can act as a natural remedy to help induce vomiting and clear out whatever is troubling their digestive system.
When a dog feels queasy, they may lose interest in their regular food but eat grass to ease discomfort.
If your dog consistently eats grass and refuses their meals, it’s important to monitor them for other signs of illness such as vomiting, diarrhea, lethargy, or changes in behavior.
This combination could mean your dog has a gastrointestinal issue requiring veterinary attention.
2. Nutritional Deficiencies
Dogs may eat grass because they instinctively crave nutrients missing from their diet, such as fiber, vitamins, or minerals.
If your dog is eating grass but not food, it could indicate that their current diet is not meeting their nutritional needs.
A lack of fiber in their meals can cause digestive problems and discomfort, leading dogs to seek grass as a source of roughage.
Similarly, some dogs may crave certain nutrients that their commercial food lacks or that their digestive tract struggles to absorb.
If this is the case, switching to a high-quality, balanced diet or supplementing with fiber may help reduce grass-eating and improve appetite.
Related: Dog eating grass and not eating (Here’s why)
3. Stress and Anxiety
Stress and anxiety can also cause dogs to eat grass but not food.
Changes in environment, routine, loud noises, or separation anxiety can lead to appetite loss.
Eating grass may become a comforting, repetitive behavior that distracts the dog from their anxiety.
Stress-related grass eating often comes with other behavioral signs like pacing, whining, excessive licking, or hiding.
If your dog is eating grass due to anxiety, it’s important to identify and reduce the source of stress, and consider consulting a veterinarian or behaviorist for support.
4. Boredom or Habit
Sometimes, dogs eat grass out of boredom or habit rather than nutritional need or illness.
Dogs left alone for long periods without stimulation may graze on grass simply to occupy themselves.
While this may not immediately cause refusal to eat food, it can lead to a preference for grass or a decrease in appetite if the dog is distracted or unmotivated to eat their meals.
Ensuring your dog has plenty of mental and physical enrichment can reduce boredom-induced grass eating.
Related: Dog eating grass all the time (Here’s why)
5. Gastrointestinal Parasites or Illness
Eating grass but not food can sometimes indicate gastrointestinal parasites or illnesses that cause discomfort or poor appetite.
Parasites like worms irritate the digestive tract and can make eating food unpleasant for dogs.
Infections or inflammatory bowel diseases may also cause similar symptoms, with dogs turning to grass as a way to soothe their upset stomachs.
If your dog shows other symptoms such as diarrhea, vomiting, weight loss, or lethargy along with eating grass but not food, seek veterinary advice promptly.
Why Is It Concerning When Dogs Eat Grass But Not Food?
While occasional grass eating is normal and usually harmless, consistent refusal to eat food while grazing on grass is concerning because it may indicate underlying health or behavioral issues that need attention.
Not eating regular food can quickly lead to nutritional deficiencies, weight loss, and weakness.
If your dog relies on grass but refuses to eat balanced dog food, they are not getting the essential proteins, fats, and nutrients required for their health.
Additionally, eating large amounts of grass can sometimes cause irritation or injury to the gastrointestinal tract.
harp grass blades may scrape the stomach or intestines, and excessive grass eating may lead to vomiting or diarrhea.
Moreover, grass may carry pesticides, herbicides, or parasites that could harm your dog if ingested frequently.
What Should You Do If Your Dog Eats Grass But Not Food?
If you notice your dog eating grass but not food, here are important steps to take:
1. Monitor Your Dog’s Behavior and Symptoms
Observe if your dog shows other symptoms such as vomiting, diarrhea, lethargy, coughing, or changes in urination.
Note whether the grass eating is occasional or constant, and if refusal to eat food is sudden or gradual.
This information will help your veterinarian diagnose the problem if medical care is needed.
2. Check Their Diet
Evaluate the quality and appropriateness of your dog’s current diet.
Are you feeding balanced, age-appropriate food? Has there been a recent change in their meals?
Try offering different food types, such as wet food, or switching to a brand with higher fiber content.
Gradually transition their diet to avoid gastrointestinal upset.
3. Reduce Stress and Provide Enrichment
If you suspect anxiety or boredom is causing grass eating and appetite loss, increase physical exercise, mental stimulation, and interactive play.
Consider calming aids or supplements recommended by your vet.
Maintain a calm feeding environment and consistent routine to encourage healthy eating habits.
4. Rule Out Medical Issues
If your dog continues to eat grass but not food for more than a day or two, or if they show additional signs like vomiting, diarrhea, or lethargy, it’s time to consult a veterinarian.
A vet can perform physical exams, stool tests for parasites, blood work, or imaging to diagnose infections, gastrointestinal diseases, or other illnesses.
5. Prevent Access to Treated Grass
Avoid allowing your dog to eat grass that may have been treated with harmful chemicals.
Opt for pet-safe areas or create grass-free zones in your yard if needed.
When to Seek Veterinary Care Immediately
Certain signs paired with eating grass but not food require urgent veterinary attention:
Persistent refusal to eat for more than 24 hours
Frequent vomiting or diarrhea
Presence of blood in vomit or stool
Severe lethargy or weakness
Signs of dehydration (sunken eyes, dry gums)
Abdominal pain or bloating
Sudden behavioral changes or distress
These could indicate serious conditions like gastrointestinal obstruction, poisoning, infections, or systemic illnesses that need immediate treatment.
Key Takeaway
Dogs eating grass but not food can mean many things—from simple boredom to serious illness.
While occasional grass eating is normal, refusal to eat regular food combined with grass munching should not be ignored.
Careful observation, dietary evaluation, and timely veterinary consultation are essential to ensure your dog’s health and wellbeing.
Common Reasons for Dog Eating Grass and Gagging
1. Gastrointestinal Irritation or Upset Stomach
One of the most common causes of eating grass and gagging is gastrointestinal discomfort. Dogs may instinctively eat grass to provoke vomiting, especially if they are feeling nauseous.
Grass can irritate the stomach lining or cause the dog to gag before or after vomiting.
If your dog is also drooling, licking its lips excessively, or has diarrhea, it could be an upset stomach.
Dogs with GI issues may show these signs alongside grass-eating and gagging:
Burping or gurgling stomach noises
Diarrhea or loose stools
Vomiting foam or bile
Reduced appetite
2. Grass Blades Stuck in the Throat
Sometimes, the physical act of eating grass causes gagging because long blades of grass get stuck in the dog’s throat or between the teeth.
This is particularly common in dogs that don’t chew the grass thoroughly. Gagging, coughing, or repeated swallowing might indicate an irritation or partial blockage.
In such cases, the dog may:
Paw at the mouth
Gag repeatedly without vomiting
Appear distressed while eating or swallowing
3. Allergies or Post-Nasal Drip
Dogs with seasonal allergies or sensitivities may already have throat irritation. When they eat grass and gag, it could worsen due to added irritation.
Allergies can cause inflammation in the nasal passages, leading to drainage that triggers the gag reflex. Combined with grass consumption, the gagging may intensify.
Other signs of allergies include:
Sneezing
Red, itchy eyes
Coughing or wheezing
Excessive licking or chewing
4. Foreign Objects or Obstructions
Dogs that eat grass often gulp it down without chewing, increasing the risk of swallowing foreign materials like twigs, mulch, or even bugs.
These items can get lodged in the throat, causing gagging after eating grass.
A lodged object may lead to:
Continuous gagging or hacking
Difficulty swallowing
Drooling
Panic or discomfort
If your dog shows these symptoms, you should seek immediate veterinary attention.
Related: Dog eating grass frantically (Here’s why)
5. Nausea from Underlying Illness
Dogs suffering from liver disease, kidney issues, or infections may experience nausea. Nauseated dogs might eat grass and gag shortly after as a result.
Nausea symptoms can include:
Lip licking
Dry heaving
Vomiting bile or food
Decreased appetite
If your dog is eating grass and showing these symptoms persistently, it may be a sign of something more serious that requires veterinary evaluation.
6. Parasites or Toxins
Eating grass in contaminated areas (e.g., sprayed with pesticides or fertilizers) may introduce toxins into your dog’s system.
Ingesting parasites or larvae found in certain grasses can also lead to gastrointestinal upset and gagging after eating grass.
These symptoms may include:
Vomiting
Diarrhea
Abdominal pain
Weakness
Be cautious about where your dog is allowed to graze, and avoid areas treated with chemicals or frequented by wild animals.
Related: Does eating grass hurt dogs?
7. Stress and Anxiety
Stress is another common but often overlooked trigger. Anxious dogs may chew or eat grass and gag due to increased salivation or muscle tension in the throat.
Stress-related symptoms include:
Pacing or whining
Excessive drooling
Panting without exertion
Clinginess or hiding
Gagging in stressed dogs may be a physical response to a tight throat or rapid breathing, which can worsen with grass ingestion.
What to Do If Your Dog Eats Grass and Gags
If you notice your dog eating grass and gagging regularly, here are the steps to take:
Observe the behavior closely: Note the frequency, intensity, and any accompanying symptoms (vomiting, lethargy, diarrhea).
Check for potential hazards: Make sure your yard is free of chemicals or sharp foreign materials.
Offer fresh water: Gagging can lead to dehydration; ensure your dog stays hydrated.
Modify the environment: Prevent access to grass if your dog has developed a habit of overconsumption or compulsive grazing.
Consult your veterinarian: Especially if gagging is persistent, frequent, or accompanied by other symptoms like vomiting or lethargy.
When to See a Vet
You should seek veterinary attention if:
Your dog gags persistently without relief
There is vomiting or diarrhea
The dog appears lethargic or refuses food
You notice signs of pain, bloating, or distress
Your dog has a history of eating foreign objects
The vet may perform diagnostic tests such as throat examination, X-rays, or bloodwork to determine the underlying cause.
Key Takeaway
While occasional grass-eating is usually normal, eating grass and gagging may indicate throat irritation, gastrointestinal issues, allergies, or stress.
It’s crucial to monitor your dog’s behavior, rule out dangerous substances or foreign objects, and seek veterinary care when symptoms persist or worsen.
A sudden change in behavior—especially gagging after eating grass—should never be ignored.
With the right care and attention, you can help your dog stay safe, healthy, and free from discomfort.