Causes of a Dog Losing Weight

Dogs lose weight for many reasons. During the summer, many dogs are more active and are not as hungry, so they often shed a few pounds. However, if a dog begins to lose weight suddenly, starts behaving out of character or shows additional symptoms, the animal may need medical attention.

  1. Addison's Disease

    • A lack of adrenal gland hormones causes Addison's disease (hypoadrenocorticism). According to Pet Place, it occurs when a pituitary tumor, a cancerous growth or certain medications damage or destroy canine adrenal glands. The disorder may be inherited in some breeds such as standard poodles. The website indicates that middle-aged, neutered male dogs are the most likely animals to develop Addison's disease. Some of the symptoms are weight loss, diarrhea, vomiting and a lack of appetite.

      Treatment options vary depending upon the severity of the disease. Severe cases often require immediate hospitalization, particularly if the dog is also experiencing kidney disorders or hypoglycemia. Addison's disease is treated with medications called mineralocorticoids, a type of steroid that stabilizes the dog's hormone levels.

    Tapeworm

    • The most common kind of tapeworm in dogs is a worm called Dipylidium caninum. Many fleas carry tapeworm eggs. Dogs that are infested with fleas bite at the fleas and sometimes swallow them. The egg hatches inside the dog and attaches itself to the intestinal lining, where it drains nutrients from the dog's body.

      Some of the symptoms of tapeworm are weight loss, scooting across the carpet or flooring and general lethargy. According to Pawprints and Purrs, the most evident symptom of tapeworm is found in the dog's stool. Small, flat white objects approximately the size of a grain of rice occasionally present themselves during a bowel movement. These objects are segments that have broken off of the tail end of the worm. They are called proglottids and they are full of tapeworm eggs. Tapeworms do not cause any serious harm to the dog and the are easily killed with de-worming medication. (see reference 2)

    Diabetes Mellitus

    • Diabetes mellitus occurs when the animal's body becomes resistant to insulin or is unable to make enough of it to meet the body's needs. The concentration of sugar in the dog's blood rises because there is not enough insulin to switch off the sugar production. Dr. Peter Graham from the Canine Diabetes website explains that the symptoms of canine diabetes are weight loss, excessive urination and excessive thirst. Some dogs experience chronic infections or develop cataracts. Diabetes is treated with daily insulin injections.