Strong Iodine Solution and Vasculitis

• Generic Name: potassium iodide
• Dosage Forms: n.a.
• Other Brand Names: IOSAT, ThyroSafe, ThyroShield, Pima, SSKI

Preoperative management of hyperthyroidism in patients with Graves’ disease undergoing thyroidectomy. American Thyroid Association (ATA), American Association of Clinical Endocrinologists (AACE), and others recommend that patients with Graves’ disease scheduled for surgery be rendered euthyroid using other antithyroid agents (preferably methimazole) and then receive potassium iodide for 7–14 days (usually 10 days) in immediate preoperative period. In exceptional circumstances when euthyroid state cannot be achieved prior to thyroidectomy (e.g., urgent need for surgery, allergy to antithyroid drugs), these experts recommend use of potassium iodide and a β-adrenergic blocking agent (e.g., propranolol) in immediate preoperative period. Preoperative potassium iodide has traditionally been used in such patients to decrease thyroid blood flow, vascularity, and intraoperative blood loss; however, some clinicians question necessity and benefits of this strategy.

Management of severe, life-threatening thyrotoxicosis (thyroid storm, thyrotoxicosis crisis) in conjunction with other antithyroid agents (e.g., methimazole, propylthiouracil), β-adrenergic blocking agents (e.g., propranolol), corticosteroids (hydrocortisone, dexamethasone), treatment of hyperpyrexia, and appropriate fluid, electrolyte, and respiratory support. Initiate other antithyroid agents first to block thyroid hormone synthesis and conversion of tetraiodothyronine (thyroxine, T4) to triiodothyronine (T3); initiate potassium iodide 1 hour after the other agents to block new hormone synthesis and thyroid hormone release.

Blockage of thyroidal uptake of radioactive isotopes of iodine (e.g., I 131) that may be released into the environment (e.g., from a nuclear power plant) to minimize the risk of radiation-induced thyroid neoplasms related to internal exposures to radioiodines (inhaled or ingested). Has no impact on uptake of other radioactive materials and does not provide protection against external irradiation of any kind.

Used as an adjunct to other protective measures (e.g., evacuation, sheltering, assurance of uncontaminated milk and food). Individuals unable to tolerate potassium iodide and individuals for whom repeat doses of the drug are a concern (e.g., neonates ≤1 month of age, pregnant or lactating women) should be given priority with regard to these other protective measures.

For use in radiation emergencies, potassium iodide is commercially available in appropriate dosage forms (see Dosage and Administration) and may also be retained in state or local stockpiles.

Decisions to recommend protective measures (including use of potassium iodide) in an emergency situation related to a US nuclear power plant reside with state and/or local government authorities responsible for radiological emergency planning and response. (See Advice to Patients.)

Used to protect thyroid during diagnostic or therapeutic use of radiopharmaceuticals or drugs that have radioactive components (e.g., iodine I 131 tositumomab; no longer commercially available in US).

Initiated prior to administration of radiolabeled diagnostic or therapeutic agent to saturate thyroid and protect it from uptake of radioiodide; continued until estimated activity of radiolabeled agent has decreased to acceptable levels after completion of the procedure or treatment.

Treatment of cutaneous sporotrichosis (localized to skin; also known as fixed cutaneous sporotrichosis) and lymphocutaneous sporotrichosis (involves skin, subcutaneous tissues, regional lymphatics) caused by Sporothrix schenckii.

Because it is inexpensive and generally effective, potassium iodide (oral solution containing 1 g/mL; also known as saturated solution of potassium iodide [SSKI]) has historically been a standard of care for treatment of cutaneous and lymphocutaneous sporotrichosis and is a drug of first choice for these infections in some resource-limited settings and countries where the disease is endemic. However, safety and efficacy for treatment of these infections not established in controlled clinical trials.

IDSA and others recommend itraconazole as drug of choice for treatment of cutaneous and lymphocutaneous sporotrichosis; terbinafine and potassium iodide (oral solution containing 1 g/mL; also known as saturated solution of potassium iodide [SSKI]) are preferred alternatives. Local hyperthermia (i.e., direct application of heat using pocket warmer, infrared or far-infrared heater, or similar device that warms tissue to 42–43°C) is another alternative for treatment of cutaneous sporotrichosis when antifungals or potassium iodide cannot be used (e.g., pregnant or nursing women).

Not effective and should not be used for treatment of extracutaneous sporotrichosis (pulmonary, osteoarticular, meningeal) or disseminated sporotrichosis; IV amphotericin B and oral itraconazole are drugs of choice for these forms of sporotrichosis.

Potassium iodide (oral solution containing 1 g/mL; also known as saturated solution of potassium iodide [SSKI]) has been used as an expectorant in the symptomatic management of chronic pulmonary diseases where tenacious mucus complicates the condition (e.g., bronchial asthma, bronchitis, pulmonary emphysema). However, efficacy not established and the drug generally has been replaced by more effective and safer expectorants.