Thyroidectomy Without Hormone Replacement: Hypothyroidism Consequences

Total thyroidectomy removes the sole source of thyroid hormone. Without levothyroxine replacement, overt hypothyroidism develops within weeks.

Symptoms

• Fatigue, cold intolerance, weight gain, constipation
• Dry skin, hair loss, brittle nails
• Bradycardia, diastolic hypertension, pericardial effusion
• Depression, cognitive slowing, myxedema
• Menorrhagia, infertility, hyperlipidemia

Severe Complications

• Myxedema coma: hypothermia, altered mental status, hypotension, respiratory failure – medical emergency.
• Accelerated atherosclerosis, heart failure.
• Infertility, pregnancy loss.

Management

• Lifelong levothyroxine (1.6 µg/kg/day typical).
• TSH monitoring every 6–8 weeks until stable, then 6–12 months.
• Adjust for pregnancy, aging, medication interactions.

Thyroid hormone replacement is non‑negotiable after total thyroidectomy.