Dog not eating or unusually tired: causes and next steps
What to do now
Seek emergency help if reduced appetite accompanies collapse, breathing difficulty, a swollen painful abdomen, repeated dry retching or suspected poisoning or swallowed object. Call promptly for vomiting, marked lethargy, pain, trouble swallowing or reduced drinking. Arrange veterinary advice when eating changes; a dog who has eaten nothing for 24 hours needs urgent assessment rather than another day of tempting meals.
Puppies, especially toy-breed puppies, frail seniors, diabetic dogs and other medically vulnerable dogs need earlier advice. Do not use the 24-hour threshold as permission to wait when anything else is wrong.
Emergency? Call a vet nowUnderstand reduced appetite, nausea, mouth pain and lethargy, with safe observations and signs that need urgent veterinary assessment.
Veterinary help in your selected country
Phone your usual vet; their recorded message should explain out-of-hours arrangements. If unavailable, contact a local emergency veterinary hospital. Confirm that it can receive your dog before travelling if possible; do not delay urgent care. Human emergency numbers are not veterinary helplines.
Open country-specific veterinary contactsUnderstanding the signs
Appetite can fall because a dog does not want food or because eating is difficult. Approaching the bowl eagerly then backing away, dropping food or chewing on one side may suggest mouth discomfort. Lip licking, drooling and repeatedly swallowing can accompany nausea. Lethargy means an unusual reduction in energy or engagement, rather than ordinary sleep after activity.
A quieter greeting, reluctance to move or hiding may be a change worth reporting. Accepting treats does not prove that a dog is well, and lack of whining does not exclude pain.
Possible causes
Dental disease, a damaged tooth, a mouth wound or swallowing problems can interfere with eating. Pain elsewhere, fever, digestive upset, pancreatitis, kidney or liver disease and medication effects can reduce interest in food. Stress or a changed routine can contribute, but should not automatically explain a sudden change in a previously reliable eater. An intact female who becomes unwell after a season may have an infected womb; increased thirst, vomiting, abdominal swelling or discharge require urgent veterinary contact, even without visible discharge.
Safe practical steps
For an otherwise comfortable healthy adult who has just declined one meal, check that food is fresh, the bowl is accessible and the eating area is quiet. Offer a small portion of their usual appropriate food; gently warming wet food may improve its smell, but check it is not hot. Avoid cycling through rich foods, salty meat, treats and supplements.
Do not force-feed, syringe food or water, give appetite stimulants or human medicines. Record what is actually eaten, including treats, and note drinking, urine, stools, weight changes and recent medicines. Ask the prescribing vet about medicines normally taken with food; do not independently change insulin or repeat a vomited dose.
What the vet may do
The vet may examine the mouth, assess hydration, temperature and pain, and check weight and the abdomen. Depending on findings, blood and urine tests, imaging or a more detailed dental examination may be appropriate. Treatment addresses the cause and may include pain relief, anti-nausea treatment, dental care or nutritional support. Very unwell dogs may need hospitalisation.
An appetite stimulant alone does not resolve every underlying problem.
Recovery, recurrence and prevention
Measure meals rather than assuming an empty bowl means recovery in a multi-dog home. Look for normal interest, comfortable eating and improving energy. Report continued poor intake, weight loss or worsening signs, even if treatment has begun. Maintain dental care, a consistent complete diet and an environment where each dog can eat without pressure. Recurring appetite changes deserve assessment, not a label of being fussy.
Common questions
Is eating treats reassuring?
It shows some willingness to eat, but does not rule out nausea, pain or illness. Tell the vet which foods are accepted and refused.
Could this be teething?
Mouth discomfort is possible, but a puppy missing meals or becoming quiet needs early advice; do not assume teething is the cause.
Should I leave food out all day?
Follow the normal feeding and hygiene routine and record intake. Prolonged access can obscure how little a dog eats, especially in a shared household.
Can stress cause it?
Yes, but sudden or persistent change also needs consideration of medical causes. Provide calm choice and do not punish or pressure a reluctant eater.
Sources and editorial review
Sources below are in English. Clinical advice is general; veterinary services and treatment availability depend on your selected country.
Editorial evidence and language checks: 24 October 2026. This information cannot diagnose your dog. No independent veterinary clinical review has taken place.