Your 14-year-old cat, Mocha, has lost half her body weight in 3 months—from 5 kg to 2.5 kg. She's ravenous, restless, and her heart races when you hold her. Her coat is unkempt. You're worried it's something serious.
Feline hyperthyroidism is caused by benign thyroid adenoma in 98% of cases. Elevated T4 confirms diagnosis. The Bloodwork OCR helps interpret thyroid panels. Classic signs: weight loss despite ravenous appetite, tachycardia, hyperactivity, unkempt coat, vomiting, diarrhea. The Vital Signs Reference shows normal feline HR 140–220 bpm—hyperthyroid cats often exceed 240 bpm.
The Endocrinology Specialist outlines options: Methimazole (oral or transdermal)—reversible, lifelong. Radioactive iodine (I-131)—curative, one-time. Thyroidectomy—surgical removal. Prescription diet (iodine-restricted)—for some cats. Cardiac and renal function should be assessed before treatment—hyperthyroidism can mask kidney disease.
With treatment, hyperthyroid cats can live years. Untreated, they develop cardiac hypertrophy, hypertension, and eventually heart failure. Early diagnosis and treatment improve quality of life.
Use Bloodwork OCR for T4 interpretation, Endocrinology Specialist for treatment discussion, Vital Signs Reference for tachycardia context.
- Weight loss + ravenous appetite in a senior cat = check T4.
- Elevated T4 confirms hyperthyroidism.
- Methimazole, I-131, surgery—treatment is highly effective.
- Assess heart and kidneys before treatment.
- Untreated leads to cardiac disease and poor quality of life.