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Weight Loss In Older Dogs: When To Worry

As dogs age, they undergo various changes, with a noticeable impact on their weight. While concerns may arise about weight gain, there's also a pressing issue of senior dogs losing weight. Our Woburn vets discuss weight loss in older dogs and when you might worry.

When Your Older Dog is Losing Weight

As dogs age, they typically gain weight, but some situations can lead to actual weight loss in your dog. If your beloved companion is losing weight, it might raise concerns about the cause, including potential muscle loss. This situation generally falls into two categories: it could indicate an underlying health condition, signaling a more significant problem, or it may result from your dog's aging process, necessitating a different dietary balance.

When is Weight Loss in Older Dogs a Concern?

When older dogs experience weight loss, an underlying health condition is often the culprit. Potential issues include liver/gallbladder disease, dehydration, dental problems, kidney disease, heart disease, diabetes, cancer, and arthritis. Your vet needs to diagnose and address each of these issues. Most root causes come with additional symptoms accompanying weight loss.

If your senior dog is shedding excess weight, note all their symptoms and promptly bring them to the vet in Woburn for a thorough examination. Below are some issues that could be affecting your pet, along with the common symptoms associated with each condition:

Liver/gallbladder disease

      • Lethargy
      • Increased thirst
      • Vomiting/diarrhea
      • Fever
      • Pain 
      • Pale or yellow gums
      • Yellowing of skin/eyes


      • Dry gums 
      • Lethargy 
      • Sunken eyes
      • Loss of skin elasticity
      • Less urination
      • Dark urine

Dental Issues

      • Excessive drooling
      • Difficulty eating/chewing
      • Bad breath
      • Swollen or bleeding gums

Kidney disease

      • Increased thirst
      • Excessive urination (may contain blood)
      • Vomiting
      • Loss of appetite
      • Pale gums
      • Lethargy

Heart disease

      • A chronic cough
      • Tires easily
      • Exercise intolerance
      • Excessive panting
      • Irregular heartbeat
      • Restlessness


      • Excessive thirst
      • Excessive urination
      • Increased appetite
      • Lethargy
      • Repeated urinary tract infections


      • Lethargy
      • Unusual bleeding
      • Lumps, bumps, or swelling
      • Distended abdomen
      • Limping or lameness
      • Unusual urination – frequency or amount


      • Wobbling
      • Lameness
      • Scuffing the toes
      • Incontinence

What should be done to feed an old dog that is losing weight?

If your vet can't identify any underlying cause for the weight loss, consider changing your dog's diet. Discuss the current diet with your veterinarian, and assess the protein, fat, and fiber levels.

If your senior dog is rapidly losing significant weight, schedule a prompt visit to your veterinarian. During the routine senior dog exam, express your concerns about your dog's weight.

My old dog is losing weight, but it's still eating

If your dog isn't showing the mentioned causes and symptoms, you might wonder why they're losing weight despite eating normally or having a regular appetite. Possible reasons for this include:

  • Changes in diet - either the brand of food your senior dog is eating or its ingredients (i.e., sometimes kibble companies will change their recipe and the number of calories per serving) 
  • Liver disease
  • Maldigestion disorders that disrupt the body's ability to break food down into nutrients 
  • Malabsorption disorders such as inflammatory bowel disease 
  • Diseases such as diabetes, which can cause loss of weight and muscle mass

Causes for Concern

While there is no need to assume the worst, most veterinarians will advise you to seek a thorough medical examination if your dog has lost 10% or more of their normal body weight.

If your dog has lost this much weight within the past year or less, your vet must conduct a full physical checkup. Your vet should know about and monitor for:

  • Changes in behavior or character
  • Signs of stress or excessive whining, pacing, or panting 
  • Constipation or a distended belly
  • Lethargy, confusion, or depression
  • Complete loss of appetite
  • Dry heaving, vomiting, or diarrhea

Note: The advice provided in this post is intended for informational purposes and does not constitute medical advice regarding pets. For an accurate diagnosis of your pet's condition, please make an appointment with your vet.

If your senior dog is noticeably losing weight, contact our Woburn vets right away to schedule an appointment for your dog. 

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