Potassium iodide

potassium iodide is evaluated for the following indications with varying evidence strength: Iodine prophylaxis in pregnancy and lactation (evidence tier A), Thyroid radiation protection in nuclear emergencies (evidence tier A), Iodine deficiency disorders (evidence tier A). See the full indication matrix with dosing and citations above on this page.

Common side effects of potassium iodide (≥ 1 in 100): Metallic taste, Epigastric discomfort, Skin redness and itching. See the Safety section for uncommon and serious reactions.

FDA category A. FDA category A at physiological doses. Supplementation at 200–250 µg daily during pregnancy and lactation is encouraged by international societies. High doses (above 500 µg daily) can cause foetal hypothyroidism and are not recommended.

Actively secreted into breast milk. Maternal supplementation at 250 µg daily ensures adequate infant iodine. High-dose potassium iodide for maternal radiation protection requires temporary breastfeeding cessation.

potassium iodide is contraindicated in: Hyperthyroidism of any aetiology; Nodular and multinodular toxic goitre; Dermatitis herpetiformis (Duhring disease); Pulmonary tuberculosis (at high doses); Iodine hypersensitivity. Full list in the Safety section.

the thyroid uses iodine continuously. Cyclical use with breaks has no physiological basis. Supplementation is continuous or not at all.

skin iodine grids and oral iodine drops are not effective iodine supplementation methods. Iodine dose in these approaches cannot be assessed. Use only certified preparations with a known dose.

high-dose potassium iodide (130 mg) is used only on official authorities' direction with proven release of radioactive iodine-131. Without such direction, use is useless and dangerous – it causes iodine-induced hyperthyroidism in some patients.