ER Vet Dr. Andrea Oncken: Medical Causes for Weight Gain in Pets

In our veterinary blog today we outline a few general health issues associated with a pet putting on a few pounds and when you should pursue veterinary care for your animal.

Pets cannot verbalize their pain, discomfort or new health symptoms. They rely on their owners to notice changes in health, physical appearance or behavior. A pet’s weight is one crucial indicator in a changing health status. WestVet Board Certified Emergency and Critical Care Specialist Dr. Andrea Oncken shared some of the medical reasons your pet may gain weight.

Weight gain and obesity can predispose your pet to concurrent health problems, such as orthopedic injuries, arthritis, diabetes, and other illnesses. The most common cause of obesity in companion animals is poor diet (i.e. feeding too much, excessive treats, feeding high fat foods) and improper amounts of exercise. If your pet is overweight, talk with your family veterinarian about a proper diet and exercise plan to help shed the pounds safely.

Occasionally, however, we may see weight gain in a pet for reasons other than improper diet and exercise. If your pet is suddenly gaining weight without any recent change in lifestyle, it is recommended to have the pet examined by a veterinarian to rule out an underlying condition.

Common medical conditions that can lead to sudden weight gain include the following:

Medications: Medications such as anticonvulsants and steroids commonly lead to increased hunger and water retention. It is common for pets on these and other medications to gain some weight.

Hypothyroidism: This is a common condition in older dogs and can lead to weight gain, lethargy, and a poor haircoat.

Abdominal conditions: If your pet is suddenly developing a distended abdomen, it is possible that there may be an abdominal condition that is causing this distension. This can include fluid build-up (congestive heart failure, hemorrhage, protein-loss), abdominal organ enlargement (stomach distension, liver, or spleen enlargement), or a neoplastic or benign mass growing within the abdomen.

Hyperadrenocorticism (Cushings): This is a disease where the body creates too much steroids, so weight gain may be a symptom of this disease.

Pregnancy: Definitely needs to be a consideration as a cause of weight gain in an intact (unspayed) pet.

All of these conditions can be diagnosed through common medical blood tests or imaging (x-rays or ultrasound). Many of these conditions are treatable, so it is recommended to seek veterinary attention early if you are noticing sudden, unexplained weight gain in your pet.