Potassium iodide

Generic Medicine Info
Indications and Dosage
Adult: As potassium iodide saturated solution (SSKI): 300 or 600 mg 3 or 4 times daily.

Radiation protection against radioactive iodine
Adult: 130 mg once daily for 10-14 days, or as directed (depending on the risk of substantial exposure).
Child: ≤1 month 16.25 mg once daily; >1 month to 3 years 32.5 mg once daily; >3-12 years 65 mg once daily; >12 years weighing <68 kg: 65 mg once daily; >12 years weighing ≥68 kg: Same as adult dose.
Nodular thyroid condition with cardiac disease, hypocomplementemic vasculitis, dermatitis herpetiformis.
Special Precautions
Patient with current or history of thyrotoxicosis, nodular goitre or latent Grave’s disease, acute bronchitis, tuberculosis, myotonia congenita, cardiac disease, adrenal insufficiency (e.g. Addison disease), acute dehydration, heat cramp. Renal impairment. Children, especially neonates (in radiation emergency). Treatment with potassium iodide as an expectorant in children should be considered carefully due to potential risks and limited evidence on efficacy. Pregnancy and lactation.
Adverse Reactions
Significant: Hypersensitivity reactions (e.g. angioedema, cutaneous/mucosal haemorrhage); thyroid-related reactions (e.g. hypo- or hyper-thyroidism, thyroid enlargement); iodism or chronic iodine poisoning (prolonged treatment); dermatitis, acne flare-ups.
Cardiac disorders: Cardiac arrhythmia.
Gastrointestinal disorders: Diarrhoea, nausea, vomiting, stomach pain or upset, salivary gland swelling or tenderness, gastrointestinal bleeding.
General disorders and administration site conditions: Fatigue, fever.
Nervous system disorders: Numbness, pain, or tingling sensation in hands or feet.
Psychiatric disorders: Insomnia, confusion, depression, nervousness.
Reproductive system and breast disorders: Impotence.
Skin and subcutaneous tissue disorders: Rash.
Monitoring Parameters
Monitor for signs and symptoms of hypo- or hyper-thyroidism; thyroid function tests in pregnant or lactating women and in children ≤3 years if repeat doses are required.
Symptoms: Iodism (e.g. burning mouth or throat, sore teeth or gums, metallic taste, increased salivation, headache, eye irritation, swollen eyelid, nausea, vomiting, diarrhoea, stomach pain, pulmonary oedema and skin lesions); gastrointestinal tract corrosion, renal damage. Management: Maintain airway and stabilise circulation. Give large amount of starch mucilage or milk as antidote. Consider lavage with starch mucilage or activated charcoal if there is no oesophageal damage. Replace electrolyte and water losses. May administer pethidine or morphine sulfate for pain. Perform tracheostomy, if necessary. Haemodialysis may reduce excessively elevated serum iodine concentrations.
Drug Interactions
Increased risk of hyperkalaemia and cardiac arrhythmia or arrest with K-containing drugs, K-sparing diuretics (e.g. amiloride) and ACE inhibitors (e.g. captopril). Increased risk of thyroid-related reactions with lithium and antithyroid agents.
Lab Interference
May interfere with thyroid function tests.
Mechanism of Action: Potassium iodide is an antidote against radioactive iodine, a possible contaminant of the environment, food and water during radiation emergency. It saturates the thyroid gland with non-radioactive iodine thereby preventing uptake of radioactive iodine. It also acts as an expectorant by increasing respiratory tract secretion and decreasing mucous viscosity.
Duration: Radiation protection: Approx 24 hours.
Distribution: Concentrated in the thyroid gland. Crosses the placenta and enters breast milk.
Excretion: Mainly via urine (89%); faeces, saliva, and sweat (small amount).
Chemical Structure

Chemical Structure Image
Potassium iodide

Source: National Center for Biotechnology Information. PubChem Database. Potassium iodide, CID=4875, https://pubchem.ncbi.nlm.nih.gov/compound/Potassium-iodide (accessed on Jan. 23, 2020)

Store between 20-25°C. Protect from light and moisture.
MIMS Class
Antidotes & Detoxifying Agents / Cough & Cold Preparations
ATC Classification
R05CA02 - potassium iodide ; Belongs to the class of expectorants. Used in the treatment of wet cough.
V03AB21 - potassium iodide ; Belongs to the class of antidotes. Used in the management of radioisotope and heavy metal poisoning.
S01XA04 - potassium iodide ; Belongs to the class of other ophthalmologicals.
Anon. Potassium Iodide. AHFS Clinical Drug Information [online]. Bethesda, MD. American Society of Health-System Pharmacists, Inc. https://www.ahfscdi.com. Accessed 08/08/2018 .

Anon. Potassium Iodide. Lexicomp Online. Hudson, Ohio. Wolters Kluwer Clinical Drug Information, Inc. https://online.lexi.com. Accessed 08/08/2018 .

Buckingham R (ed). Iodine. Martindale: The Complete Drug Reference [online]. London. Pharmaceutical Press. https://www.medicinescomplete.com. Accessed 08/08/2018.

Iostat Tablet (Anbex Inc.). DailyMed. Source: U.S. National Library of Medicine. https://dailymed.nlm.nih.gov/dailymed/. Accessed 15/01/2018.

Potassium Iodide 65 mg Tablets (G.L. Pharma GmbH). MHRA. https://products.mhra.gov.uk/. Accessed 04/09/2018.

SSKI Potassium Iodide Solution (Upsher-Smith Laboratories, LLC). DailyMed. Source: U.S. National Library of Medicine. https://dailymed.nlm.nih.gov/dailymed/. Accessed 08/08/2018.

ThyroShield (Fleming & Company, Pharmaceuticals). DailyMed. Source: U.S. National Library of Medicine. https://dailymed.nlm.nih.gov/dailymed/. Accessed 08/08/2018.

ThySat 65 mg Tablets (Hameln Pharmaceuticals Ltd.). MHRA. https://products.mhra.gov.uk/. Accessed 04/09/2018.

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