Hyperthyroidism

Treating hyperthyroidism can unmask hidden CKD because hyperthyroidism artificially increases kidney blood flow. Both are common in senior cats.

Both are endocrine disorders of older cats; thyroid disease alters glucose metabolism

Alters glucose metabolism; resolving thyroid disease improves diabetic regulation

Untreated thyroid excess causes cardiac changes that can progress to heart failure and sudden death.

— medical cause of house soiling

Treating the thyroid often resolves the hypertension entirely.

Post-thyroidectomy parathyroid damage causes hypocalcemia

— thyroid disease must be ruled out

In cats, malignant thyroid tumors cause hyperthyroidism

Untreated thyroid disease leads to hypertension, which can cause sudden blindness.

Chronic intermittent diarrhea is a common sign.

Excessive thirst, also an early sign of CKD.

Chronic intermittent vomiting, also seen in CKD and intestinal lymphoma.

The hallmark sign, shared with CKD and lymphoma.

I-131 is the definitive cure for feline hyperthyroidism

Thyroid-specific prescription diets exist for management.

Used when thyroid treatment alone does not resolve hypertension.

Primary medication for managing feline hyperthyroidism

Screening recommended for all hyperthyroid cats.

T4 level is the diagnostic standard.

The measured hormone for diagnosis and monitoring.

Excess thyroid hormone also disrupts blood pressure.

Risk factor: canned food diets (BPA in can lining) and iodine-restricted diets for treatment.

— overactive thyroid in older cats