About potassium iodide
Thyroid-blocking inorganic iodide
Used for
- Short-term protection of the thyroid after radioactive iodine exposure, alongside evacuation or sheltering guidance.
- Prevention of radioactive iodine uptake by the thyroid during a nuclear emergency.
Usual adult dose
130 mg once daily while exposure risk continues, as directed by public health officials.
Usual dose in children
Dose depends on age: under 1 month, 16 mg; 1 month–3 years, 32 mg; 3–18 years, 65 mg once daily. Follow emergency instructions.
Common side effects
- Nausea, vomiting, diarrhea, or stomach pain
- Rash or swelling of salivary glands
- Rarely, allergic reactions or abnormal thyroid function
Important warnings
- Use only when directed by public health or emergency authorities; it does not protect against other radiation.
- Avoid repeated doses unless directed, especially in newborns and older adults.
- Use cautiously with thyroid disease, iodine allergy, or kidney problems.
- Seek emergency care for breathing difficulty or facial swelling.
Pregnancy
Use only when directed by authorities. Repeated doses may affect the baby's thyroid; newborn thyroid testing may be needed.
Breastfeeding
Use only when directed. Repeated doses may affect the infant's thyroid; infant monitoring may be needed.
Interactions
- ACE inhibitors or potassium-sparing diuretics may increase blood potassium.
- Lithium may increase risk of thyroid problems.
- Antithyroid medicines or radioactive iodine treatment may interact with its thyroid effects.
AI-generated from general medical knowledge, not from this product's official leaflet. It may be incomplete or out of date. Not medical advice — ask a pharmacist or doctor before making any decision.