If your dog won't eat or drink, consider the followings:
What has your dog been doing for the previous 2-3 days?
Could they have eaten anything they shouldn't have?
Did you just bring them into a new environment?
Did your dog have surgery, or any major lifestyle changes?
When your dog won't eat or drink, make a note of any other symptoms that accompany a dog's loss of appetite and anorexia. For example: lethargy, nausea, diarrhea, excessive drooling.
While your dog's occasional refusal to eat is normal, prolonged lack of appetite and especially thirst can be a sign of a serious health problem. Here are some of the potential reasons why your dog wont eat or drink, and what to do about it.
The dog might have tummy ache or feeling slightly unwell. If you suspect that your dog isn’t eating because they feel slightly unwell, check their temperature and observe them for the day. If your pet shows obvious signs of illness, call or visit a veterinarian.
Maybe your dog is simply not hungry or thirsty. Even though anyone who has ever cared for a Labrador Retriever will tell you that this is impossible, sometimes, a dog may simply be not hungry. In that case, they should begin showing signs of hunger within 24 hours. This is not necessarily a sign of any sickness. Thirst is a different matter, and your pooch should drink at least within 12-14 hours.
If, after that period of time has passed, the dog won't eat or drink anyway, this may be a symptom of something more serious than just not being hungry or thirsty
Most doggy snacks, even the healthy treats, are high in calories. When you feed your dog too many treats, it's not surprising that they get “full”.
If your dog wont eat or drink because they have had too many treats, you will obviously remember that this may be the reason. If you did not feed your pet any treats, ask family members if they did. A dog who refuses food and water because they have eaten too many dog treats will be fine after skipping a meal or eating a smaller portion later than usual. And don’t be surprised if your dog has an upset tummy due to eating tons of calorie dense treats, too. So maybe you should just give it time.
Sure your dog is not taking any medication? If a dog is currently taking any medications, and especially if they started on a new one, this could be the cause of their loss of appetite and thirst. Take a look at the medication insert for your pet's medication and read through the potential side effects. Call a vet if you're unable to figure this out by yourself. When a dog won't eat or drink, new medications are very common to be the cause of this, but generally, this side effect will taper off. In the meantime, try tempting the dog with boiled chicken and rice, food toppers or chicken broth. If your dog has been on medication for a while and continues to experience anorexia, talk to your vet about alternative medications.