Why Is My Senior Dog Not Eating?

Appetite changes in senior dogs (generally 7+ years for large breeds, 10+ for small breeds) should always be taken more seriously than in younger dogs. While a young healthy dog skipping a meal is rarely concerning, seniors have less metabolic reserve and are far more likely to have an underlying medical cause.

Dental disease is one of the most underdiagnosed causes of appetite loss in older dogs. Years of accumulated tartar, gingivitis, tooth root abscesses, and loose teeth make eating painful. Many owners don't realize their senior dog has dental disease because dogs are stoic — they don't cry out, they just gradually eat less or switch to eating only soft food.

Chronic kidney disease (CKD) is extremely common in senior dogs and causes nausea, reduced appetite, increased thirst and urination, and weight loss. It develops gradually and may not show obvious symptoms until significant kidney function is lost. Regular blood work in seniors can catch it early.

Cancer affects approximately 50% of dogs over 10 years old. Many cancers cause gradual appetite loss, weight loss, and lethargy before any other symptoms appear. Hemangiosarcoma, lymphoma, and oral tumors are among the most common.

Other causes: liver disease, pancreatitis (acute or chronic), cognitive dysfunction (confusion about routine including mealtimes), medication side effects (NSAIDs, antibiotics), constipation, and depression (loss of a companion pet or family member).

Changes in smell and taste sensitivity occur with aging, just as in humans. Senior dogs may lose interest in food they previously loved simply because it doesn't smell or taste as strong to them anymore.