Increased Appetite in Dogs

Hunger and the feeling of being full after eating (satiety) are controlled by the central nervous system. Abnormalities in the CNS can cause increased appetite, as can several other factors such as stress, an underlying disease, or cancer. Because appetite changes are so common in many illnesses and situations, diagnosing the reason for it can be a complex process. Polyphagia can indicate serious disease. Any alteration in your pet’s eating behavior should be checked by the veterinarian.

Increased appetite is known as polyphagia in veterinary terms. If your dog seems to be continuously hungry and his behavior dictates that he requires food in excess of the norm, further investigation is warranted. This is especially true if the appetite has recently increased. A visit to the veterinarian is needed in order to diagnose an underlying cause, and to determine how the insatiable appetite is affecting his weight (another important marker of canine health).

Prompt action in dealing with an increased appetite is conducive to determining the exact cause. Polyphagia complications can range in severity. The following symptoms can indicate that your dog must be seen by the veterinarian without delay.

• Weight changes can include both loss or gain
• Excessive thirst
• Frequent urination
• Exhibiting behavior indicating constant hunger
• Lethargy
• Abdominal bloating

If the polyphagia is due to an underlying disease, you may see symptoms such as those listed below. Symptoms will vary depending on the cause:

• Depression
• Neurological signs can include pacing, circling, blindness
• Lethargy
• Muscle weakness
• Panting
• Soft stool or diarrhea
• Trembling
• Vomiting or regurgitation
• Increased thirst

Types

Polyphagia can be classified as follows.

• Primary
• Caused by destruction of the satiety center, for example, trauma. This is rare.
• There will likely be additional neurological signs of a CNS disease

• Secondary
• More common than primary polyphagia
• Diseases, parasites and the improper diet can result in secondary polyphagia

• Drug Induced
• Corticosteroids and anti seizure medicine, for example, can increase food intake

If your canine companion is showing signs of constant hunger, the situation can be worrisome, and can often lead to very unfavorable behavior on the part of your dog (such as begging). In order to return your pet to his normal state of well-being, you will want to take him to the veterinarian without delay. Causes for the increased appetite are great in number. Some are listed below.

• A lesion in the central nervous system
• Hypoglycemia
• Low-calorie or unbalanced diet
• Overfeeding
• Learned behavior of begging for food
• Stress can cause your dog to increase eating habits
• Infection
• Continual living in a low environmental temperature
• Pregnancy or lactation
• Increased exercise
• An endocrine or hormone related disease like diabetes mellitus or hyperadrenocorticism
• Malabsorption or maldigestion of food due to illness or parasites
• Pancreatic atrophy
• Increased rate of gastric emptying
• Cancer
• Medications like thyroid supplements, corticosteroids sedatives or anticonvulsants

The veterinarian will, under most normal circumstances, begin with a physical examination while discussing your observations and concerns. Possible findings may include muscle wasting, alopecia (hair loss), ataxia (loss of control of bodily movements), and abdominal or hepatic enlargement.

Laboratory tests can be great indicators of why your dog seems to have an insatiable appetite. The tests can reveal various results.

• Complete Blood Count
• Presence of anemia will be evaluated through red blood cell count
• An increase in white blood cells could point to intestinal parasitism or hyperadrenocorticism (Cushing’s Disease)
• Serum Biochemical Profile
• Changes to glucose, proteins and enzymes may be discovered
• Increase in alkaline phosphatase can mean Cushing’s Disease, recent corticosteroid administration or diabetes mellitus
• Urinalysis
• We will check for blood, protein and glucose
• Poorly concentrated urine can occur in e.g. diabetes and Cushing's Disease
• Fecal Flotation
• This procedure is done to check for parasites

Additional diagnostic imaging might be needed, in the form of a radiograph, ultrasound, endoscopy, CT scan or MRI scan.

The treatment protocol for your canine family member will vary depending on the underlying cause of the polyphagia. The veterinarian has the knowledge to help you deal with any sort of at home therapy required for successful resolution of the appetite changes.

For example, a drug-induced increase in appetite may be indeed temporary, and will wane with time, even with the continued use of the prescribed medication.

In the instance of an apparent insatiable appetite caused by stress or learned behavior, you will receive direct advice and best practices on how to deal with the problem. The veterinary caregiver may suggest behavioral therapy for a habitual eater. A dog suffering from a stress-induced neverending desire to eat may benefit from the simple removal or reduction of the stressor. No doubt, the veterinarian will ask you to feed your dog only as per the caloric requirements to maintain the good health of your pet. Don’t be discouraged; behavioral issues take time to resolve. Patience and kindness are the best remedies.

If there is a serious underlying disease, of course, it must be dealt with and in turn, the appetite problem should also resolve. For example, diabetes mellitus will require insulin injections and dietary adjustments. A parasitic infestation will be eradicated with medication. Diseases like cancer may involve treatment in the form of surgery, radiation or chemotherapy, and perhaps all three.

The prognosis, by all means, is dependent on the cause of the polyphagia. Continual communication with the veterinary caregiver will be part of the home care and management. The veterinarian will advise on the need for repeat blood tests, imaging follow-up and dietary advice. Return visits to the clinic will depend upon the initial cause of the polyphagia. As always, working together with the veterinary specialist is best for the continued comfort and welfare of your dog.