If your dog is always a picky, slow eater, and he goes on strike for a meal or two, there is usually nothing urgent to be worried about – but do mention this to your veterinarian at your dog’s next wellness examination. The pickiness may indicate a chronic problem that will improve with treatment, such as a cracked tooth or a mild case of acid reflux.
If, in contrast, your dog normally has a good appetite, but suddenly stops eating his food, you should be concerned – and even more so if you dog has any other signs of illness, such as lethargy, panting, fever, signs of pain or discomfort, or diarrhea. In that case, get him to a vet! Any time our dogs change their normal behavior, there is likely something wrong that needs investigation. Ignoring early symptoms usually costs us, and our dogs.
Potential causes of a lack of appetite
There are many reasons why a dog may be reluctant to eat:
- Dental disease, including broken teeth and infected gums, may cause pain when eating.
- Ear infections are another source of pain that can lead to reluctance to eat, especially hard food.
- Other forms of pain can cause a dog to stop eating. Panting, trembling, walking hunched over, sleeping more than usual, reluctance to run or jump, and irritability can all be signs of pain.
- Dogs who are sick, including dogs with cancer and those undergoing chemotherapy, are often reluctant to eat. Kidney disease, for example, can cause nausea and gastric ulceration due to excess acidity.
- If you recently opened a new bag of your dog’s regular food and he turns up his nose at it, pay attention; this could be a sign that the food is spoiled or moldy, and possibly dangerous. Do not add flavor enhancers or human meal leftovers to tempt him into eating the food he rejected, because if it turns out that the food is dangerous, he may be harmed by eating it! Even if only one dog in your household doesn’t want to eat and the rest are fine with the food, it would be safer to get a new bag and see if that solves the problem. If your dog eagerly accepts the new food, take the rejected food back to the store!
- Many medications list nausea and anorexia as potential side effects. If your dog is on medication and becomes reluctant to eat, talk to your vet to see if a substitute is available, or if there is a way to make the pills easier on your dog’s stomach. For example, some meds that are normally given away from meals can be given with food instead to help with stomach upset.
Warning: In some cases, loss of appetite can be a symptom that the medication you are giving is dangerous. This is especially true in the case of NSAIDs (non-steroidal anti-inflammatory drugs) such as Rimadyl, Deramaxx, and even aspirin. Corticosteroids such as prednisone can cause gastrointestinal ulceration and associated inappetence.
If your dog is on any of these drugs and stops eating, you should discontinue the medication immediately (don’t stop prednisone without your vet’s OK). Get your dog to the vet, especially if other symptoms are present, such as vomiting, diarrhea, black or tarry stools, or lethargy.