iodine + potassium iodide: clinical use

Prescribing considerations

• Confirm the intended route and formulation; the cutaneous and oral products are not interchangeable.
• Restrict the topical product to minor wounds; avoid prolonged application, large open wounds and occlusive dressings.
• The oral solution’s SmPC advises caution in children.

Contraindications and cautions

• Hypersensitivity to iodine or iodides applies to both products.
• Topical tincture: newborn infants, thyroid disorders and concurrent lithium therapy.
• Aqueous oral solution: pregnancy and lactation.

Monitoring

• Review thyroid status after systemic iodine exposure.
• Iodine can interfere with thyroid-function tests; account for recent exposure when interpreting results.
• Assess promptly for iodism, hypersensitivity or thyroid dysfunction if symptoms develop.

Clinical pharmacology

Topical iodine is a broad-spectrum antiseptic and is only slightly absorbed through intact skin. Orally, iodine is converted to iodide, concentrated in the thyroid and eliminated mainly in urine. It crosses the placenta and enters breast milk.

Formulation and product differences

• Iodine Tincture BP is an alcoholic cutaneous solution for external use and is listed as discontinued on eMC.
• Aqueous Iodine Oral Solution BP is a water-based oral solution for specialist pre-operative thyroid management.
• The formulations differ in composition, excipients, route, licensing and safety restrictions.