How should thyroid storm be treated?

Thyroid Storm Treatment

Thyroid storm requires immediate multi-drug therapy without waiting for laboratory confirmation—begin treatment the moment you suspect the diagnosis, as mortality rises dramatically with any delay. 1, 2

Immediate Treatment Algorithm

Step 1: Block New Thyroid Hormone Synthesis (Start First)

Administer propylthiouracil (PTU) as the first-line thionamide because it uniquely blocks both thyroid hormone synthesis AND peripheral conversion of T4 to T3. 1, 2, 3

• PTU is superior to methimazole in thyroid storm specifically because of its dual mechanism 1, 3
• If PTU is unavailable, use methimazole 20 mg every 4-6 hours, though it lacks the peripheral conversion blocking effect 2
• In patients unable to take oral medications, rectal administration via enema or suppository is a viable alternative route 4

Step 2: Block Thyroid Hormone Release (Wait 1-2 Hours After Thionamides)

Administer saturated solution of potassium iodide (SSKI) 5 drops every 6 hours OR sodium iodide 500-1000 mg IV every 8 hours, but ONLY after starting thionamides. 1, 2

• Critical pitfall: Never give iodine before thionamides—this can paradoxically worsen thyrotoxicosis by providing substrate for new hormone synthesis 1
• Alternative options if iodine is contraindicated: Lugol's solution or lithium 2

Step 3: Control Adrenergic Symptoms and Block Peripheral Conversion

Propranolol 60-80 mg orally every 4-6 hours is the preferred beta-blocker because it also blocks peripheral T4 to T3 conversion in addition to controlling cardiovascular symptoms. 1, 2

For Hemodynamically Unstable Patients:

Use esmolol with a loading dose of 500 mcg/kg IV over 1 minute, then maintenance infusion starting at 50 mcg/kg/min, titrating up to maximum 300 mcg/kg/min. 1, 2

• Esmolol's ultra-short half-life allows rapid titration and immediate reversal if cardiovascular collapse occurs 1
• This is especially important in patients requiring concurrent vasopressor support 2

If Beta-Blockers Are Contraindicated:

Use diltiazem 15-20 mg (0.25 mg/kg) IV over 2 minutes, then 5-15 mg/h maintenance infusion. 1, 2

• Avoid beta-blockers in severe heart failure 2

Step 4: Reduce Peripheral T4 to T3 Conversion

Administer dexamethasone 2 mg IV every 6 hours to block peripheral conversion and treat possible relative adrenal insufficiency. 1, 2

Essential Supportive Care

• Oxygen therapy as needed 1, 2
• Antipyretics for fever control (avoid aspirin as it increases free thyroid hormone) 2
• Aggressive fluid resuscitation with large-bore IV access 2
• Identify and treat precipitating factors: infection, surgery, trauma, labor/delivery, medication non-adherence 2, 5

Hospitalization and Monitoring

All patients require hospitalization; severe cases need ICU admission with immediate endocrinology consultation. 1, 2

Critical Monitoring Parameters:

• Cardiac complications: heart failure, arrhythmias (especially atrial fibrillation) 1, 2
• Agranulocytosis from thionamide use—presents with sore throat and fever 1, 2
• Hepatic dysfunction 5
• Central nervous system disturbances 5

Special Population: Pregnancy

The treatment protocol is identical to non-pregnant patients—maternal mortality risk outweighs fetal concerns. 1, 2

• Monitor fetal status with ultrasound, nonstress testing, or biophysical profile based on gestational age 2
• Avoid delivery during active thyroid storm unless absolutely necessary due to extremely high maternal and fetal mortality risk 1, 2
• PTU is preferred over methimazole in pregnancy 1
• For atrial fibrillation complicating thyrotoxicosis in pregnancy, administer heparin (not warfarin) for anticoagulation 2

Refractory Cases

If conventional therapy fails, consider therapeutic plasma exchange to rapidly reduce circulating thyroid hormone levels. 6

• This is reserved for patients with inadequate response to standard multi-drug therapy 6
• In extreme circumstances, emergency thyroidectomy may be necessary 7, 4

Post-Acute Management

• Monitor thyroid function every 2-3 weeks after initial stabilization 1, 2
• Watch for transition to hypothyroidism, which commonly occurs after thyroid storm treatment 1, 2
• Plan definitive treatment of underlying thyrotoxicosis once the acute crisis resolves 7

Common Pitfalls to Avoid

• Never delay treatment waiting for laboratory confirmation—thyroid storm is a clinical diagnosis 2, 5
• Never administer iodine before thionamides—this worsens hormone synthesis 1
• Never use aspirin for fever control—it increases free thyroid hormone 2
• Never attempt delivery during active thyroid storm in pregnant patients unless absolutely necessary 1, 2
• Do not overlook precipitating factors—infection, surgery, trauma, and medication non-adherence are common triggers that require concurrent treatment 2, 5, 8