Companion Cat Hyperthyroid Treatment Options

Multiple treatment options for feline hyperthyroidism allow individualised welfare-optimised management.

Key Facts

Radioactive iodine (I-131) is curative in 95% of cases with a single treatment
Methimazole medication controls the condition but requires lifelong daily administration
Hill's y/d iodine-restricted diet can control hyperthyroidism in some cats
Thyroidectomy is effective but surgery carries anaesthetic risks in older cats

Welfare Considerations

Untreated hyperthyroid cats deteriorate progressively — losing weight, developing heart disease, and experiencing hypertension-related complications. Each treatment option has welfare implications: radioactive iodine requires isolation but is curative; daily medication requires reliable administration; dietary therapy requires strict compliance. Discussing all options with a vet and choosing based on individual cat and owner circumstances enables welfare-optimised management.

What You Can Do

Discuss all treatment options with a veterinary internist or specialist
Ensure consistent daily medication if choosing medical management
Monitor treated cats for hypothyroidism which may follow treatment
Keep regular veterinary checks for kidney function alongside hyperthyroid management