An iodine-restricted prescription diet offers an alternative to medication or surgery for managing feline hyperthyroidism, but its welfare implications — including very strict feeding requirements — require careful consideration for individual cats.
Iodine-restricted dietary management avoids the welfare costs of daily medication or the acute welfare impacts of surgery and post-operative recovery. For cats that accept the diet, management is non-invasive and stress-free. However, the strict requirement that the diet be the sole food source imposes significant constraints on the cat lifestyle — outdoor access must be eliminated to prevent prey ingestion, treats and supplements are excluded, and in multi-cat households, complete feed separation is required. For cats that previously had outdoor access or varied diets, these restrictions represent a welfare trade-off. Owner compliance with strict dietary requirements is a significant challenge and non-compliance renders the approach ineffective.