Not Eating in Dogs

Periodically skipping a meal is normal in dogs, and does not necessarily indicate a problem. If your dog is not eating, it could be indicative of his dislike of his current food or a new food, or he may have gotten into something that upset his stomach. But when your dog has stopped eating many meals in a row, or completely, it can indicate a more serious problem, especially in the presence of other symptoms, such as weight loss, vomiting, diarrhea, lethargy, or behavioral changes. 

There are many reasons why your dog may have lost his appetite. These can include:

• Stress or anxiety
• Pain 
• Gastrointestinal disease 
• Heart, liver, or kidney disease
• Immune-mediated disease
• Hypothyroidism
• Addison’s disease
• Infections
• Cancer
• Dental issues
• Side effects of medications
• Poisoning

Some of the more common reasons why a loss of appetite might be occurring in your dog include:

Stress 

Stress or an increased state of anxiety can result from a number of situations, such as a new home or family member, the loss or absence of a family member, a trip, or even just a thunderstorm. Stressful situations or a generalized anxiousness can cause your dog to be too nervous to eat.

Pain 

Pain can be located anywhere in the body and can be an indicator of a more serious condition. Where the pain is, and how severe it appears to be, will lead your veterinarian to discover the cause. Pain could be originating in the mouth, esophagus or stomach, or even in the joints, where it can dissuade your dog from crouching to eat. 

Gastrointestinal Disease 

A mild gastrointestinal discomfort can come about from your dog eating a food that didn’t agree with his system, or from constipation, and will usually pass. However, if your dog continues to refuse food, or is not defecating, it may indicate a worse condition that needs medical attention. Conditions such as gastroesophageal reflux disease or a dietary allergy are often undiagnosed conditions that can be treated. 

Systemic Diseases

These are illnesses that involve the entire body, many of which can cause a loss of appetite. Common diseases of this type include heart, liver, and kidney diseases. Immune-mediated diseases refer to conditions wherein the immune system attacks itself and the body and can include rheumatoid arthritis, hemolytic anemia, and systemic lupus erythematosus. Hypothyroidism results from a lack of thyroid hormone production and can affect the entire body. Addison’s disease is caused by a reduced production of certain hormones, such as cortisol. Cortisol helps with stress control, but since the adrenal glands are unable to produce enough, affected dogs can find any change in their routine stressful.

Infections

A bacterial, viral or parasitic infection can cause a loss of appetite. While certain pathogens can target gastrointestinal organs and reduce function, parasites, in particular, can invade organs and multiply, causing pain and swelling.

Cancer

Cancer can affect any part of the body, and many types of cancer carry a loss of appetite as a symptom. In advanced stages, this is coupled with many other signs, as the cancerous cells multiply, invading organs and compromising the functionality of the body.

Dental Issues 

Often, dental discomfort can be the reason why your dog has stopped eating. As plaque builds up on teeth, it can cause periodontal disease, such as severe infections and gingivitis. A broken tooth could also cause your dog to stop putting pressure on his teeth.

Side Effects of Medications 

If your dog has recently been administered medications, vaccines, or supplements, you may see a loss of appetite. This type of cause is often temporary, and depends on the amounts of medicines your dog has been given, as well as the duration of use. Any side effects from such treatments should always be reported to your veterinarian.

Poisoning 

A toxic poisoning that can cause your dog to stop eating can come from any number of plants, chemicals, toxic foods, and non-prescribed drugs that he may have been exposed to. While some toxic ingestions may cause mild symptoms, the risk of a life threatening condition is high in many types of poisonings.

Monitor your dog during this time. You can attempt to get your dog to eat by offering canned food, cooked boneless, skinless chicken or lean ground beef, cooked eggs, or chicken broth low in salt. Stay away from fatty foods, and highly seasoned foods.

If your dog still refuses to eat for more than 24 to 48 hours, then it is time to seek medical care, especially if he is showing any other symptoms. While many reasons may not seem to be an emergency, many types of poisonings can result in death if not treated in time.  If a loss of appetite is left untreated for a lengthy amount of time, it can lead to malnourishment and further debilitation.

Your veterinarian will likely perform a physical exam, where he may detect areas of pain or dental concerns. Other tests can confirm the presence of infections, hormone irregularities, toxic chemicals or alkaloids, cancerous tumors, or other conditions that may be affecting your dog.

Fluids and supportive care may be given, and any offending medications will no longer be administered. The course of treatment then depends on the cause. Antibiotics, antivirals, and antiparasitics may be administered for infections, while hormone therapy is useful for some systemic diseases. Cancer treatments vary, but generally include tumor removal and chemotherapy.  Dental cleaning and procedures may be needed for periodontal disease or injuries, while broken teeth may benefit from a change in chew toys. Anxious dogs may need behavioral modification, and can also benefit from calming supplements. And lastly, your veterinarian will likely recommend dietary changes to get your dog eating again.

While many diseases are impossible to predict, and therefore prevent, you can ensure the safety of your dog in other ways. Keeping toxic plants, chemicals and foods away from your dog can reduce the risk of poisoning. Routine exams can often catch serious conditions while they may be treatable. Getting your dog vaccinated regularly can protect against many bacterial and viral infections, while using preventative treatments can shield your dog from many types of parasites. And brushing your dog’s teeth cannot only alert you to a broken or loose tooth that may become painful or infected, but it can lower the risk of periodontal disease.

Treatment for a loss of appetite in your dog can vary in price depending on the cause. While costs can range in price from $350 to treat Addison's disease to $5,000 for a plant poisoning, an average veterinary bill for this condition is around $1,000.