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Why is my senior dog losing weight but eating and drinking a lot?
Updated on September 23rd, 2025
Pet's info: Dog | Parson Russell Terrier | Female | spayed | 15 years and 9 months old
My 15yr old female jack Russel is losing weight rapidly. She still eats the same amount, but drinks a lot of water a day. She is wormed regularly. She enjoys a good walk still.
5 Answers
Most Helpful Answer
Answered By Andrea M. Brodie, DVM
Veterinarian
Published on December 6th, 2016
Polydipsia and Polyuria (drinking and urinating excessively) and weight loss are typical for these two diseases. It is easy to diagnose with a blood test. Please take Jasmine to your vet for a blood test. Once diabetes is diagnosed, your vet can explain the therapy (most likely insulin injections, which are easily done and nothing to be feared), and diet. If kidney disease is diagnosed, she will have to take some medications and go on a special renal diet and likely regularly get fluids injected under the skin. Please take her to the vet soon .
1Pet Parents found this answer helpfulRelated Answers from Veterinarians
Answered By Dr. Melanie, BVSc MS
Veterinarian
In an old dog like Jasmine, losing a lot of weight despite eating along with increased drinking could be due to diabetes. Unfortunately, cancer is always a possibility as well in old dogs. I would take Jasmine into the vet first thing in the morning. The vet can do a physical exam, routine blood tests, a urinalysis, and possibly x-rays to diagnose what is causing her weight loss. Once a cause is found, treatment can be decided. If she has diabetes, for example, it can be treated with daily insulin injections.
1Pet Parents found this answer helpful
Answered By Jenny, DVM
Veterinarian
Published on December 28th, 2017
At his age I would worry about kidney disease and diabetes. He may have pancreatitis or infection causing the blood diarrhea as a result of a previous disease. He will need to have blood work done to test for these disease as they do have good medicine to keep things under control since non have a cure. All of these can compromise other organs and be fatal if they go untreated but your vet can hospitalize and provide what treatments are needed along with prognosis once a diagnosis is made.
1Pet Parents found this answer helpful
Answered By Dr. Leigh, DVM
Veterinarian
Published on September 20th, 2017
Poor Pakalolo! Excessive drinking and urinating can be a sign of many diseases including diabetes, kidney disease, liver disease, infections, Cushing's disease, Addison's disease, cancer, etc. She should be examined by a vet for blood-work and a urinalysis to determine the cause of her problem. Once diagnosed, your vet can determine the best way to treat. As for the hard time getting up, she may have some arthritis in her hips and need an anti-inflammatory to help.
1Pet Parents found this answer helpful
Answered By Dr. Melanie, BVSc MS
Veterinarian
Published on September 18th, 2018
Poor Nella! This decrease in appetite could be due to a number of problems such as dental disease, liver disease, kidney disease, systemic illness, infection, inflammation, or injury. The drinking a lot more could be caused by kidney disease or diabetes to name two causes. I would take her into a vet today or tomorrow. The vet can do a physical exam, geriatric blood panel, and urinalysis as a start to try to figure out what is going on with her. Once a cause is diagnose, the vet can discuss treatment options. Best of luck, I hope this helps!
1Pet Parents found this answer helpful