It’s natural for dogs to drink water throughout the day—but if your dog is drinking a lot of water and vomiting afterward, it could signal a more serious health concern.
Whether the vomiting is immediate or delayed, it’s important to determine the underlying cause.
We outline the common causes of dog drinking a lot of water and vomiting, what you can do at home, and when to seek veterinary help.
Dog Drinking a Lot of Water and Vomiting — Why It Happens
Dogs may vomit after drinking a lot of water due to nausea, overhydration, gastrointestinal upset, infections, or systemic conditions like diabetes or kidney disease.
Some dogs may drink too quickly when overheated or dehydrated, triggering regurgitation or vomiting. Persistent vomiting always warrants a closer look.
Common Causes of Dog Drinking a Lot of Water and Vomiting
Drinking Too Fast or Too Much at Once
Some dogs gulp down large amounts of water quickly—especially after exercise or excitement.
This rapid intake can irritate the stomach or trigger regurgitation.
Slowing down access to water and offering small amounts at a time can help.
Nausea or Gastrointestinal Upset
Dogs with nausea may drink water in an attempt to soothe their stomach, only to vomit shortly after.
Common causes include dietary indiscretion, sudden food changes, or viral infections.
Look for drooling, lip licking, or lack of appetite as additional clues.
Kidney Disease
Dogs with kidney disease often experience both increased thirst and vomiting.
Toxins build up in the bloodstream when kidneys don’t function properly, causing gastrointestinal symptoms.
Other signs may include weight loss, lethargy, or bad breath. Blood tests can confirm the diagnosis.
Read more: Dog Drinking a Lot of Water and Peeing a Lot (What it means)
Diabetes Mellitus
Uncontrolled diabetes can lead to excessive thirst and vomiting, especially if blood sugar levels become dangerously high.
Vomiting in a diabetic dog is always serious and can indicate a condition like diabetic ketoacidosis.
Watch for increased appetite, weight loss, or changes in urination.
Infections or Illness
Systemic infections, such as leptospirosis or pancreatitis, can lead to increased drinking and vomiting.
These illnesses often present with fever, abdominal pain, and lethargy.
Prompt diagnosis and treatment are vital to prevent complications.
Heat Exhaustion or Dehydration
Overheating may cause dogs to drink large volumes of water quickly and then vomit.
Vomiting in this case may be paired with heavy panting, collapse, or weakness.
Immediate cooling and veterinary care are essential for dogs showing signs of heatstroke.
What to Do If Your Dog Is Drinking Excessively and Vomiting
Remove access to large amounts of water temporarily and offer small sips every 15–30 minutes.
Withhold food for a few hours to allow the stomach to settle, then reintroduce a bland diet if vomiting stops.
Monitor your dog’s hydration, energy, and behavior closely.
If vomiting continues or other symptoms arise, contact your veterinarian right away.
Never ignore vomiting that recurs more than once in 24 hours or is paired with lethargy or other abnormalities.
When to Call or Visit Your Vet
Contact your vet urgently if your dog:
Vomits repeatedly or forcefully
Has blood in vomit or stool
Acts lethargic, disoriented, or weak
Refuses to eat or drink
Has a history of diabetes, kidney disease, or recent toxin exposure
Your vet may perform bloodwork, urinalysis, X-rays, or an ultrasound to identify the cause.
Read more: Dog Drinking a Lot of Water and Then Throwing Up (How to spot danger early)
Key Takeaway
When a dog drinks excessive water and vomits, it may be reacting to nausea, illness, or a serious medical condition.
Keep water intake moderate and consistent, and seek veterinary care if vomiting is persistent or combined with other warning signs. Fast action can make a significant difference in your dog’s recovery and comfort.