From the Guidelines
Potassium iodide (KI) is the recommended iodide for hyperthyroidism, particularly in preparation for thyroid surgery or in thyroid storm emergencies, as stated in the 2002 American Family Physician study 1. The typical dose is 50-100 mg three times daily, usually administered as SSKI (saturated solution of potassium iodide) drops, with each drop containing approximately 50 mg of iodide. Some key points to consider when administering potassium iodide include:
- Treatment should begin 7-14 days before thyroid surgery and continue for no more than 2-3 weeks total due to the risk of escape from the Wolff-Chaikoff effect.
- For thyroid storm, higher doses (250-500 mg every 6 hours) may be used alongside antithyroid drugs and beta-blockers.
- Potassium iodide works by inhibiting thyroid hormone release through the Wolff-Chaikoff effect and by reducing thyroid vascularity, making surgery safer.
- Side effects may include metallic taste, salivary gland swelling, rash, and gastrointestinal disturbances.
- Potassium iodide should be taken with food or milk to minimize stomach irritation, and patients should be monitored for iodism symptoms.
- This treatment is contraindicated in pregnancy except in emergencies, and patients with iodine allergy should not receive it. It's worth noting that while other studies, such as those published in the Annals of Internal Medicine in 2015 1, discuss screening and treatment for thyroid dysfunction, they do not provide more recent or higher-quality evidence regarding the use of potassium iodide for hyperthyroidism than the 2002 American Family Physician study.
From the Research
Iodide Treatment for Hyperthyroidism
- The use of iodide in the treatment of hyperthyroidism is a topic of discussion in several studies 2, 3, 4, 5, 6.
- According to some clinical guidelines, iodine, combined with antithyroid drugs, is recommended as an initial pharmacologic treatment for thyroid storm 6.
- A study published in 2025 found that early potassium iodide (KI) use was associated with lower in-hospital mortality in patients with thyroid storm and Graves' disease 6.
- However, the same study found that KI use was not significantly associated with in-hospital mortality in patients without Graves' disease 6.
- The study also found that length of stay was shorter and total hospitalization costs were lower in the KI group compared with the non-KI group 6.
Types of Iodide Treatment
- Potassium iodide (KI) is a commonly used form of iodide treatment for hyperthyroidism 6.
- Radioactive iodine (131I) is also used to treat hyperthyroidism, particularly in cases of toxic nodular goitre 4.
- The choice of treatment depends on the underlying diagnosis, the presence of contraindications to a particular treatment modality, the severity of hyperthyroidism, and the patient's preference 3.
Indications for Iodide Treatment
- Iodide treatment is indicated for patients with hyperthyroidism who are at risk of thyroid storm 6.
- It is also indicated for patients with Graves' disease, particularly those with ophthalmic manifestations 2, 4.
- In some cases, iodide treatment may be used in combination with antithyroid drugs or surgery to manage hyperthyroidism 2, 3, 4, 5.