If your dog is eating grass and being sick, you’re not alone in wondering whether this behavior is normal or a sign of something serious. Many dog owners report seeing their pets munch on grass only to vomit shortly afterward.
This combination of symptoms can point to several underlying causes.
We outline why dogs eat grass, what it means when they vomit afterward, and when to seek veterinary help.
Table of Contents
Dog Eating Grass and Being Sick: Why It Happens
When a dog eats grass and then becomes sick, especially vomiting shortly afterward, it’s often because the dog is trying to relieve an upset stomach or nausea. Eating grass can irritate the stomach lining, prompting vomiting that helps the dog feel better temporarily.
While occasional grass eating followed by mild sickness can be normal, frequent or severe vomiting may indicate underlying issues such as gastrointestinal infections, dietary problems, parasites, or even poisoning.
Causes Behind Dog Eating Grass and Being Sick
1. Gastrointestinal Infections
Viruses, bacteria, or parasites can all upset your dog’s digestive system.
When your dog is feeling unwell, eating grass and vomiting might be their body’s response to the irritation or infection.
These infections can lead to nausea, and the grass acts as a natural way for dogs to purge their system.
However, this isn’t a cure and may make things worse if left untreated.
Related: Dog eating grass and not eating (Here’s why)
2. Dietary Indiscretion
Dogs love to explore the world with their mouths. Sometimes they eat garbage, spoiled food, or even toxic substances like chocolate or plants.
This “dietary indiscretion” can upset their stomach, leading to dog eating grass and being sick episodes.
3. Food Allergies or Intolerance
If your dog recently changed diets or started a new brand of dog food, they may react poorly to new ingredients.
Some dogs develop sensitivities to grains, beef, chicken, or artificial additives.
This can cause stomach upset, leading to grass consumption followed by vomiting.
4. Parasites
Intestinal parasites such as roundworms, hookworms, or giardia can irritate your dog’s digestive tract.
Dogs may eat grass as a response to the discomfort, which leads to vomiting.
If your dog is eating grass and also shows signs of weight loss, bloated belly, or loose stool, a fecal test may be needed.
5. Toxin Ingestion
If your dog has ingested a toxic substance—such as a household cleaner, pesticide-treated grass, or poisonous plant—they may eat grass and vomit as their body tries to expel the toxin.
This is a medical emergency. If your dog ate grass and is now vomiting repeatedly or shows signs like shaking, panting, or unresponsiveness, seek emergency veterinary care immediately.
Related: Dog eating grass and coughing (Here’s why)
How to Handle Dog Eating Grass and Being Sick
If your dog eats grass occasionally and throws up once in a while, it may not require urgent medical attention.
However, here’s what you can do:
1. Monitor Behavior Closely
Note the frequency and circumstances of the dog eating grass and being sick.
Is it after meals? During walks? When stressed? Keeping track helps you identify patterns.
2. Check Their Diet
Ensure your dog’s food is high in fiber, balanced in nutrients, and free from ingredients they may be intolerant to.
You may also consider switching from dry to wet food if hydration is an issue.
3. Reduce Access to Treated Lawns
If your dog eats grass during walks or in your yard, make sure the area is free from pesticides, herbicides, or fertilizers.
Ingesting treated grass can cause poisoning.
4. Provide Mental Stimulation
Boredom can lead to grass eating. Make sure your dog gets enough exercise, toys, and interaction to reduce stress or idle behavior.
5. Visit a Veterinarian
If vomiting continues or is accompanied by other symptoms like diarrhea, lethargy, or poor appetite, schedule a vet visit.
They may perform diagnostic tests such as blood work, fecal exams, or X-rays.
When to See the Vet Immediately
You should seek veterinary care if your dog eating grass and being sick is paired with the following:
Vomiting more than once a day
Presence of blood in vomit or stool
Refusal to eat or drink
Signs of dehydration (dry gums, sunken eyes)
Seizures or collapse
Symptoms persisting for more than 24 hours
Young puppies and senior dogs are especially vulnerable and should be examined sooner rather than later.
Final Thoughts: Dog Eating Grass and Being Sick
A dog eating grass and being sick can be a puzzling behavior, but it’s not always a cause for alarm.
While some dogs simply like the taste or texture of grass, vomiting afterward suggests a deeper reason, such as nausea, digestive upset, or even an underlying illness.
Keep an eye on your dog’s behavior, monitor how often it happens, and look for any additional symptoms.
If the issue becomes frequent or is accompanied by other concerning signs, don’t hesitate to consult your veterinarian.
By addressing the root cause and taking proactive steps, you can help keep your dog happy, healthy, and free from the cycle of grass-eating and vomiting.