Questions? We're here to help. Health advisors on staff. Call us toll-free at (866) 947-6789.

Blister Pack Box of 20 RadBlock Potassium Iodide Tablets

RadBlock - Potassium Iodide Tablets (KI)

Regular price
Sale price

Info: 65 mg KI Tablets, Blister Packs of 20 Per Box.

Due to increased demand, Radblock is currently unavailable from the manufacturer. Please see the equivalent New Roots Herbal 65mg Potassium Iodide for nuclear emergency use which is in stock.

Product Notes:

RadBlock is a high potency iodine/potassium iodide supplement. This special combination of iodide and iodine helps saturate the tissues of the body with sufficient levels of iodine for disease prevention. A salt of stable (non-radioactive) iodine, potassium iodide helps block radioactive iodine.

RadBlock has been sold to Canadian nuclear power plants and the Government of Canada since 2003.

Iodine is an essential element that is mainly used in the production of thyroid hormones by the thyroid gland (although other organs in the body also require iodine in order to function normally).

Potassium iodide (chemical formula KI) is used also as a nutritional supplement to help the thyroid block and resist radioiodine exposure from the environment and ingestion of food. RadBlock thyroid blocking agent is intended for use in nuclear emergencies involving the release of radioiodine.

Potassium iodide (KI) use in Canada: RadBlock™ may be issued by authorities to those in an area experiencing a nuclear emergency or potential emergency. KI pills are for use in addition to standard preventative measures for avoiding exposure to radiation including evacuation, shelter, and the careful care and consumption of food and water.

Health Canada Natural Product Number: 02248172 (KI Canada).

Product Best Before May 2034.

RadBlock KI tablets are coated to mask bitterness. Store sealed package at 15°C to 30°C. Protect from light and moisture. Consult your healthcare professional before use and read the detailed warnings below.

Though not intended for radiation blocking, other iodine supplements include Alterra Io-Med (Potassium Iodide & Iodine), Truehope Nascent Iodine, and Biotics Research Liquid Iodine Forte.

RadBlock Ingredients:

Each tablet contains:

65 mg of potassium iodide, which provides these amounts of the two elemental ingredients in that compound:
- 15.3 mg Potassium
- 49.7 mg Iodine

Non-medicinal ingredients: Hydroxypropyl methylcellulose, titaniumdioxide, polyethylene glycol 400, polysorbate 80, FD&C Yellow #5, FD&C Blue #2, FD&C Yellow #6.

Suggested Usage:

RadBlock is intended for use in nuclear emergencies involving the release of radioiodine. Prepare to be safe: You can buy potassium iodide to have on hand, but you should only use RadBlock in consultation with your healthcare professional or following the guidance of local authorities.

Take as soon as possible after exposure. Take one dose* every 24 hours until risk of exposure to radiations from inhalation or ingestion no longer exists, or as directed by healthcare authorities. (*The recommended dosage varies by age or weight, as explained below.)

Take with a full glass of liquid to help reduce stomach upset. The tablets or portions thereof may be crushed and mixed with water, milk, juice, broth, flat soda, low fat chocolate milk, jam, or baby formula -- just ensure the full dose is taken.

Repeat dosing in children under 1 month of age or in pregnant or breastfeeding women should be avoided.


Pregnant or breastfeeding women: Take 2 tablets daily, whole or crushed. (Total dose: 130 mg). Take only one dose; do not repeat.

Infants under 1 month old: Take 1/4 of a tablet daily, dissolved in formula (total dose 16 mg)

Children aged 1 month to 3 years: Take 1/2 tablet daily, crushed in food or fluids (total dose 32.5 mg)

Children and teens aged 3 to 18 (or up to 70 kg in weight): Take 1 tablet daily, whole or crushed (total dose 65 mg)

Adults (18 and up) or adolescents weighing over 70 kg: Take 2 tablets daily, whole or crushed (total dose 130 mg).

Further Reading on Usage of KI Iodine Pills:

Ontario Health - Potassium Iodide (KI) Guidelines (PDF)

US FDA Guidance - Potassium Iodide as a Thyroid Blocking Agent in Radiation Emergencies (PDF)


Do not take more than the recommended dose within 24 hours (more will not help, and will increase the risk of side effects).

Anyone who is allergic to iodine, or who has dermatitis herpetiformis, or hypocomplementemic vasculitis, or who have thyroid disease and a nodular thyroid condition (such as a multi-nodular goiter) in addition to heart disease should not take potassium iodide anti-radiation pills.

Patients with other thyroid conditions such as Grave's disease, autoimmune thyroiditis, or nodular thyroid disease without heart disease should take Rad Block as directed above (under advisement from your healthcare practitioner). Please contact your doctor if you take it for longer than 3 days.

In case of an allergic reaction (swelling of arms, face, legs, lips, tongue; difficulty breathing, speaking or swallowing; shortness of breath and/or appearance of severe rash); contact your doctor or public health authority immediately. In case of overdose, get medical help or call a Poison Control Centre immediately.

Keep potassium iodide out of the reach of children. 

UPC / Barcode: 627843494676