Iodine × Levothyroxine

Severity: MODERATE Evidence: well-established

Mechanism

Excess iodine can paradoxically inhibit thyroid hormone synthesis (Wolff-Chaikoff effect) and interfere with thyroid medication.

Effect

Altered thyroid function; hypothyroidism in susceptible individuals

Management

Avoid high-dose iodine supplements (>1mg/day) with thyroid disease. Monitor TSH.

Source

Leung AM, Braverman LE. Thyroid 2012

⚠️ MODERATE INTERACTION: Monitor closely if this combination is used.

Disclaimer

This interaction record is for informational purposes only and does not constitute medical advice. Always consult a healthcare provider before starting or stopping any supplement or medication.