Waking up to find your dog vomiting white foam during the night can be unsettling. While it might be a one-off incident, repeated nighttime vomiting could signal a health concern that shouldn’t be ignored.
We outline the common causes of dog vomiting white foam at night, what you can do at home, and when to seek veterinary help.
Dog Vomiting White Foam at Night — Why It Happens
Nighttime vomiting of white foam in dogs can result from an empty stomach, acid reflux, indigestion, or underlying illness. Dogs may go too long without food, lie in certain positions that worsen reflux, or experience illness that manifests during rest periods. Repeated episodes warrant investigation.
Common Causes of Dog Vomiting White Foam at Night
Empty Stomach or Hunger Pukes
When dogs go long hours between meals, stomach acid can build up and irritate the lining.
This often results in white or yellowish foamy vomit—especially early in the morning or late at night.
It’s more common in dogs fed once per day or with long fasting intervals.
Adding a small bedtime snack or shifting to twice-daily feeding can often help.
Acid Reflux (Gastroesophageal Reflux)
Just like humans, dogs can suffer from acid reflux. At night, when lying down, stomach contents may move upward into the esophagus.
This irritates the throat and leads to foamy vomiting, especially after long rest periods.
Symptoms may include lip licking, swallowing noises, or reluctance to eat.
Antacids, smaller meals, and elevating food bowls may offer relief—under veterinary guidance.
Related: Dog vomiting foam and not eating (Here’s why)
Bilious Vomiting Syndrome
This condition causes dogs to vomit yellow or white foam due to bile and stomach acid irritating the gut lining during fasting.
It typically occurs in the early morning hours or late at night when the stomach is empty.
Affected dogs often appear otherwise healthy, but ongoing vomiting can damage the esophagus.
Small late-night meals and dietary adjustments may resolve the issue.
Inflammatory Conditions or Gastritis
Chronic inflammation of the stomach lining—due to infection, toxins, or underlying disease—can cause overnight vomiting.
Foam may appear due to a mixture of mucus, bile, and gastric fluids.
Your dog may show signs like restlessness, poor appetite, or licking the floor at night.
Persistent or worsening symptoms require veterinary evaluation and possible medication.
Ingested Irritants or Foreign Bodies
If your dog has access to garbage, plants, or objects during the day, they may vomit hours later—often while resting.
Vomiting white foam can occur as the body tries to expel irritants from the digestive tract.
You may not notice symptoms until nighttime when digestion slows.
A physical exam or imaging may be needed if ingestion is suspected.
Related: Dog vomiting and not eating (Causes and what to do)
What to Do If Your Dog Is Vomiting White Foam at Night
Monitor when the vomiting happens—note if it’s always after a long period without food or only during certain positions.
Offer a small, bland snack (like plain boiled chicken or rice) before bed to buffer stomach acid.
Make sure your dog isn’t accessing trash, toys, or yard debris that could trigger vomiting.
Keep a log of frequency, time, and appearance of vomit to share with your vet.
Avoid giving over-the-counter meds unless prescribed, as some can worsen stomach upset.
When to Call or Visit Your Vet
Seek veterinary care if your dog:
Vomits white foam regularly or more than once overnight
Loses interest in food or has repeated nausea
Shows signs of dehydration, dry gums, or lethargy
Also has diarrhea, gagging, or abdominal discomfort
Is a puppy, senior, or has a chronic health condition
A physical exam, bloodwork, and imaging may be needed to rule out more serious causes.
Read more: Dog Vomiting White Foam and Lethargic (Is it something serious?)
Key Takeaway
Vomiting white foam at night is often related to an empty stomach or reflux, but repeated episodes may signal something deeper.
Try feeding a small bedtime meal and monitor your dog closely. If symptoms persist, contact your vet to identify and address the cause early.