Loss of Appetite in Dogs

Loss of appetite, or “anorexia”, in dogs is a sign that can be indicative of a variety of possible underlying problems. The underlying cause could range from a minor stressor to a life-threatening illness. A pet choosing to eat little or no food as the result of an upset stomach or stress may begin eating again within 24 hours. However, loss of appetite for longer than 1-2 days can be a sign of medical emergency and should not go untreated.

Refusing to eat more than two meals is uncommon for most dogs. Loss of appetite is a serious indicator of an underlying illness, which can vary from depression to cancer. if you notice a change in your dog's eating habits, schedule an appointment with a veterinarian immediately. It is especially important to respond quickly to a refusal to eat in dogs that are usually "chow hounds", and normally have good appetites.  

Signs of loss of appetite in dogs include:

• Eating less food than normal
• Refusing to eat food
• Refusing to eat treats
• Lack of interest in food
• Trying to eat but unable
• Weight loss
• Weakness/lethargy
• Vomiting

Types

• Pseudo-anorexia – The pet wants to eat, however cannot due to a physical problem.
• True anorexia – The pet has no desire to eat.

A variety of issues can cause loss of appetite in dogs:

Psychological Causes of Anorexia

• Depression
• Stress
• Undesirable food
• Environmental change
• Dietary change
• Change in daily routine

Physical Causes of Anorexia

• Medication
• Infection (bacterial, viral, parasitic)
• Cancer
• Pain
• Toxin exposure
• Dental problems
• Cardiovascular disease
• Gastrointestinal disease or blockage
• Endocrine disorder
• Autoimmune disease
• Respiratory illness
• Neurological disease

It is important to note whether any environmental or dietary changes have occurred that may be causing the loss of appetite in your pet. Possible stressors could include moving to a new home, having house guests for a visit, a family member leaving for a period of time, getting a new pet, loud noises (fireworks, gunshots, thunder) or change in diet.

If your pet is demonstrating loss of appetite, you may want to try feeding a bland diet (boiled chicken breast and white rice) and see if the appetite returns. If you have changed diets recently, try going back to the old diet or add a bit of low-sodium chicken broth or vegetable broth to stimulate appetite. Monitor your pet for 24 hours and if low appetite continues or if you notice the pet is not having bowel movements or is having diarrhea and/or vomiting, visit the veterinarian for an examination.

The veterinarian will want to know when the loss of appetite began, and whether your pet tries to eat but can’t or doesn’t try at all. Any recent changes to the diet or environment can be important information.

The physical examination will include an examination of the mouth, teeth and throat and abdominal palpitation for possible pain or masses. Laboratory diagnostics may include blood testing to detect any abnormalities in liver, kidney, and other organ function. A fecal exam can detect the presence of intestinal parasites. Radiographs will aid in visualization of any abdominal or chest abnormalities. Endoscopy can be used to help visualize the condition of the throat, stomach lining and upper small intestine.

You can attempt to stimulate appetite at home by warming the pet’s food slightly or adding warm water to kibble (increasing smell and palatability). Be very certain that the food is not too hot and stir microwaved food well to distribute heat evenly after warming. You may also try adding canned food or low-sodium chicken broth (or vegetable broth) to kibble. A pet may respond to hand feeding with fingers or a spoon better than eating from a bowl.

If the pet refuses to eat after a 24-hour period, veterinary treatment will be necessary.

Supportive Care

If the pet has not eaten in a few days, intravenous or subcutaneous fluid therapy will rehydrate the pet and provide electrolytes. Syringe feeding or a feeding tube may be required for pets who haven’t eaten in 2-3 days. An appetite stimulant such as mirtazapine or cyproheptadine can aid in boosting appetite.

Treatment of the Underlying Issue

Once the condition that is causing the loss of appetite is identified, proper treatment of the condition will be initiated. This may involve oral medications, dental procedure and/or surgery.

Refeeding

Once the pet is stabilized, a refeeding plan will be put into place. Normally, a bland diet will be offered for 2-3 days with small portions given frequently throughout the day. The diet will then transition to a regular diet gradually over one week

Be sure to follow your veterinarian’s instructions on refeeding and diet management carefully. The gastrointestinal tract is often sensitive after periods of not eating and your veterinarian’s dietary instructions will address this. Let your veterinarian know if appetite is not considerably improved within 1-2 days after release and monitor bowel movements and behavior carefully.

Recovery from anorexia depends on the ability to detect and treat the underlying cause quickly. Prognosis may be good with early detection and pets can regain appetite in a day or two after the underlying cause is addressed.

A high-quality diet is essential for keeping your dog happy and healthy. Digestive problems and food allergies can be expensive to treat. Compare pet health insurance plans to save more than $270 a year on vet care.