Hypothyroidism is a common endocrine disorder in dogs causing weight gain, lethargy and skin problems that respond excellently to lifelong thyroid hormone replacement.
Hypothyroidism causes a progressive deterioration in quality of life that owners often attribute to normal aging rather than recognising as a treatable disease. Affected dogs experience fatigue, cold intolerance, mental dullness and skin discomfort that meaningfully impairs their daily experience. The treatment transformation is one of veterinary medicine's most satisfying outcomes — dogs that were lethargic and uncomfortable become energetic and comfortable within weeks of appropriate levothyroxine supplementation. Regular monitoring of thyroid hormone levels ensures optimal dosing throughout the dog's life.