FDA-filed SPL labeling · retrieved through openFDA

Potassium Iodide

Potassium iodide is an iodine supplement used across multiple products to block radioactive iodine from entering the thyroid gland during a nuclear radiation emergency, and — as SSKI oral solution — to loosen thick mucus in chronic lung conditions.

Brand names IosatThyroSafeThyroShieldSSKI brand of Potassium IodideKali iodatum +2 more
Rx/OTC Forms 4 Route Oral
Dr. Brian Staiger, PharmD, BCPS
Reviewed by Last reviewed Jul 10, 2026
🧬 Where this information comes from Click to expand

The clinical label records used on this page are FDA-filed Structured Product Labeling (SPL) retrieved through openFDA. We identified 10 clinical label sets within the page’s selected clinical scope after exact ingredient or ingredient-combination matching and applicable route/form matching. Forms, routes, brands, labelers, strengths, and NDC product-record counts are built separately from matching FDA National Drug Code Directory records. The linked DailyMed document is a representative official source for verification, not the page’s only clinical source. View the linked label on DailyMed →

At a glance
Linked label effectiveOct 3, 2025
Clinical labels in scope 10
AvailabilityRx/OTC
Earliest approval/marketing year 1979
FDA-listed product records 56
Boxed warningYes
How we combine label and product data →
No current FDA shortage listed · checked Sep 20, 2026
Potassium Iodide at a glance The quick version — the full detail is in the Patient Information Guide below.
💊
HelloPharmacist Editorial Team Bottom Line
Potassium iodide tablets and oral solution (Iosat, ThyroSafe, Potassium Iodide solution) are thyroid-blocking medicines to be used only during a nuclear radiation emergency, exactly as public officials direct. SSKI oral solution serves a separate purpose — helping thin thick mucus in chronic lung conditions like asthma and bronchitis. Never take the emergency products on your own or more than once every 24 hours, and check with a doctor first if you have thyroid disease, a heart condition, or an iodine allergy.
⚠️ FDA Boxed Warning — the FDA’s strongest safety alert

Only take potassium iodide when public officials tell you to during a nuclear radiation emergency. It is meant to protect your thyroid gland from absorbing radioactive iodine that may be released into the air. The protection from each dose lasts about 24 hours, so take it once a day for as long as officials advise — usually 10 to 14 days. Taking more than one dose per day will NOT give you more protection, and it raises your risk of side effects. Always use it alongside other emergency measures recommended by authorities. Do not take it if you are allergic to iodine.

Read the full warning on DailyMed →

📖 Potassium Iodide: Patient Information Guide

A plain-language walkthrough of Potassium Iodide — what it treats, how it works, how it’s taken, side effects, warnings and interactions. Tap any section to expand it.

🎯What it's used for

Potassium iodide is used for two distinct purposes depending on the product.

  • Nuclear radiation emergency (thyroid blocking): Iosat tablets, ThyroSafe tablets, and Potassium Iodide oral solution are all approved to help prevent radioactive iodine from being taken up by the thyroid gland during a nuclear radiation emergency. These products are to be used only when directed by public officials, alongside other emergency measures.
  • Expectorant for chronic lung disease: SSKI (potassium iodide oral solution) is approved as an expectorant for the symptomatic treatment of chronic lung diseases where thick mucus is a problem — including bronchial asthma, bronchitis, and pulmonary emphysema. This is a separate, non-emergency use specific to SSKI.
⚙️How it works

For emergency thyroid protection, potassium iodide works by flooding the thyroid gland with stable, non-radioactive iodine. The thyroid can only hold a limited amount of iodine at a time, so when it is already full of safe iodine, it cannot absorb the harmful radioactive kind that may be released during a nuclear emergency. This significantly reduces the risk of thyroid damage, especially in children, who are most vulnerable.

As an expectorant (SSKI), potassium iodide is thought to increase fluid secretions in the respiratory tract. This makes thick, sticky mucus thinner and easier to cough up and clear from the airways.

💊How it's taken

How potassium iodide is taken depends entirely on which product and which use applies to you.

  • Iosat and ThyroSafe tablets (emergency use): Take once by mouth every 24 hours — no more than one dose per day — only when instructed by public officials. Tablets can be taken whole or crushed and mixed into liquids. Follow your prescriber's and officials' guidance on how many days to continue.
  • Potassium Iodide oral solution (emergency use): Use the dropper provided to measure the correct amount; take once every 24 hours as directed by public officials.
  • SSKI oral solution (expectorant use): Diluted in a full glass of water, juice, or milk and taken 3 to 4 times daily with food or milk to minimize stomach upset. Use for only as long as necessary.
🤒Side effects — in detail

Most people who take potassium iodide at recommended doses for a short time tolerate it well, but side effects can occur.

  • Nausea, vomiting, diarrhea, or stomach pain
  • Metallic taste in the mouth
  • Swelling or tenderness of the salivary glands
  • Skin rash or hives
  • Headache and fever
  • Swelling of the hands or feet
  • In rare cases: overactive thyroid, underactive thyroid, or thyroid enlargement (goiter)
  • With prolonged or high-dose use: iodism (chronic iodine poisoning) — symptoms include burning mouth or throat, severe headache, metallic taste, and eye irritation

Seek emergency help immediately for any signs of a serious allergic reaction — such as trouble breathing, swelling of the mouth or throat, wheezing, or irregular heartbeat and chest pain. Stop use and call a doctor if you develop swelling of the face, hands, or feet, fever with joint pain, or a skin rash.

⚠️Warnings & precautions
  • Use only when told by public officials (emergency products): Iosat, ThyroSafe, and Potassium Iodide oral solution are not for everyday use. Taking them without official direction or taking more than one dose per day does not provide more protection and raises the risk of harm.
  • Iodine allergy: Do not take any form of potassium iodide if you have ever had an allergic reaction to iodine. A serious allergic reaction can cause breathing trouble, swelling of the mouth or throat, and wheezing — call 911 immediately if this happens.
  • Certain medical conditions: People with nodular thyroid disease with heart disease, hypocomplementemic vasculitis, or dermatitis herpetiformis must not take potassium iodide, as these conditions increase the risk of serious side effects.
  • Thyroid effects: In rare cases, potassium iodide can cause the thyroid to become overactive or underactive, or to enlarge. People with existing thyroid disease face higher risk. Newborns under 1 month are especially prone to hypothyroidism (underactive thyroid).
  • Iodism (chronic iodine poisoning): Using high doses or continuing treatment longer than necessary can lead to iodism. Signs include burning in the mouth or throat, metallic taste, severe headache, and increased saliva. Stop the medicine and seek medical care if these appear.
🔀What it interacts with

Potassium iodide can interact with certain medications in ways that are important to know before you start taking it.

  • Lithium or antithyroid drugs: Taking these alongside potassium iodide can increase the chance of developing an underactive thyroid or a goiter (enlarged thyroid gland).
  • Potassium-containing medicines, potassium-sparing diuretics (water pills), or ACE inhibitors (a common type of blood pressure medicine): Combining these with potassium iodide can raise potassium levels in the blood to dangerously high levels, which may cause life-threatening irregular heartbeat or cardiac arrest.

This is not a complete list of interactions. Always talk with your doctor or pharmacist before starting, stopping, or changing any medication.

📋Before taking it
  • Do not take if you have a known allergy or sensitivity to iodine or iodides
  • Do not take if you have nodular thyroid disease combined with heart disease
  • Do not take if you have hypocomplementemic vasculitis or dermatitis herpetiformis
  • If you are pregnant or breastfeeding, take only as directed and contact your doctor as soon as possible
  • Babies under 1 month of age are at higher risk for hypothyroidism (underactive thyroid) — use with extra caution and medical guidance
  • People with any thyroid disease (other than nodular thyroid disease with heart disease) should follow dosing directions and contact a doctor promptly
  • Tell your doctor if you take lithium, antithyroid medicines, potassium supplements, potassium-sparing diuretics, or ACE inhibitors
🚑If you take too much

Serious toxicity from too much potassium iodide is uncommon, but some people can be very sensitive and react quickly — even shortly after taking a dose. Signs of too much iodide can include severe swelling (angioedema), swelling of the throat (laryngeal edema), and skin bleeding. If iodism (chronic poisoning) occurs with long-term or high-dose use, symptoms usually go away after stopping the medicine; drinking plenty of fluids and salt can help the body clear iodide faster. In case of overdose, get medical help or call Poison Control right away.

📡Pharmacodynamics — effects in the body

When taken for a nuclear emergency, potassium iodide saturates the thyroid gland with stable iodine, blocking it from taking up radioactive iodine from the environment. Because the thyroid can only store a limited amount of iodine, filling it up with the safe form prevents dangerous radioactive iodine from getting in. The protective effect of each dose lasts approximately 24 hours. When used as an expectorant (SSKI), it increases secretions in the airways, reducing the stickiness of mucus.

📦How to store it

Store at 20° to 25°C (68° to 77°F); excursions permitted to 15° to 30°C (59° to 86°F) . dispense in tight, light-resistant containers with child-resistant closures.

📄 Written from Potassium Iodide’s FDA-approved label information, summarized in plain language with AI, and reviewed by our pharmacy team before publication. Every point is grounded in that labeling — nothing is invented. How we use AI →

🩺 Pharmacist Counseling Corner

Quick, plain-English answers to the questions patients ask most about Potassium Iodide — the kind of thing our pharmacy team would talk through with you at the counter.

Should I keep potassium iodide at home just in case, or only take it if there's actually an emergency?
It's reasonable to have it on hand if public health authorities in your area recommend it — especially if you live near a nuclear facility. But the key rule is: only take it when public officials actually tell you to. Taking it ahead of time or 'just in case' on your own doesn't help and can cause side effects. Wait for the official instruction.
What if I take an extra dose? Will it protect me better?
No — taking more than one dose every 24 hours will not give you more protection. Your thyroid can only hold a certain amount of iodine at a time, so once it's full, extra doses just sit in your body and raise the risk of side effects like thyroid problems or allergic reactions. Stick to one dose per day, as officials direct.
I have a thyroid condition — is it safe for me to take this?
It depends on your specific condition. If you have nodular thyroid disease along with heart disease, you should not take potassium iodide. If you have other types of thyroid disease, you can follow the standard dosing directions, but you should contact your doctor as soon as possible after taking it, since you're at higher risk for thyroid-related side effects. When in doubt, call your doctor.
How do I give this to a young child or baby who can't swallow a tablet?
Both Iosat and ThyroSafe tablets can be crushed into a fine powder and dissolved in water, then mixed with milk, juice, flat soda, or infant formula to make a drinkable liquid. The dose given depends on the child's age and weight — public officials and the package insert will guide you. ThyroSafe's liquid mixture can be kept in the fridge for up to 7 days, so you can prepare it in advance. Always follow the age-specific dosing in the package insert carefully.
What side effects should I watch out for, and when should I get help fast?
Common side effects include stomach upset, nausea, metallic taste, and salivary gland swelling — these are uncomfortable but not emergencies. Call a doctor if you notice swelling of your face or hands, fever with joint pain, or a skin rash. Get emergency help immediately — call 911 — if you have trouble breathing, swelling of your mouth or throat, wheezing, or chest pain with an irregular heartbeat. Stop taking the medicine and act fast if any of those serious symptoms appear.
I take a blood pressure medicine — is it safe to combine it with potassium iodide?
It depends on the type. If you take an ACE inhibitor (a common blood pressure medicine like lisinopril or enalapril) or a potassium-sparing diuretic (water pill), combining it with potassium iodide can raise your potassium levels to dangerously high levels, which can cause serious heart rhythm problems. Let your doctor or pharmacist know what you're taking so they can advise you safely.
Is Potassium Iodide available over the counter?
Both — Potassium Iodide is sold both over the counter and by prescription, according to its FDA labeling. Lower strengths or certain forms are often available without a prescription, while higher strengths or specialized forms still require one. Ask your pharmacist which version is right for you.
When was Potassium Iodide first available?
Potassium Iodide has been available in the United States since at least 1979, based on FDA approval history (Drugs@FDA) and product marketing records.
Who makes Potassium Iodide?
Potassium Iodide is supplied by 20 manufacturers listed in the FDA NDC Directory, including Boiron, Anbex Inc., Merck KGaA.

💬 Answers drafted from Potassium Iodide’s FDA-approved label information, summarized in plain language with AI, and reviewed by our pharmacy team before publication. Grounded in that labeling — nothing is made up. How we use AI →

🧰 Keep exploring

💊 How Potassium Iodide comes

Potassium Iodide is available in 4 forms. Different forms and brands can have different approved uses, doses, schedules, and directions. Follow the instructions for your exact product, and do not switch forms without guidance from your prescriber or pharmacist.

Oral solution

By mouth
Brands Kali Iodatum 1x Sski
How this form is used
What it may be used for
  • Potassium Iodide oral solution is a thyroid-blocking medicine used only during a nuclear radiation emergency to prevent radioactive iodine from being absorbed by the thyroid gland
  • SSKI (potassium iodide oral solution) is used as an expectorant to help loosen thick mucus in chronic lung diseases such as bronchial asthma, bronchitis, and pulmonary emphysema
Important instructions
  • Potassium Iodide oral solution: use the included dropper to measure the correct amount; take once every 24 hours only when directed by public officials
  • Potassium Iodide oral solution: do not take more than 1 dose in 24 hours
  • SSKI: dilute in a full glass of water, fruit juice, or milk and take 3 to 4 times daily; take with food or milk to reduce stomach upset
  • SSKI: use only for as long as needed to produce the desired effect
Available strengths 3 strengths
15 FDA-listed product records

Tablet

By mouth
Brands Iosat ThyroSafe
How this form is used
What it may be used for
  • Iosat is a thyroid-blocking medicine used only during a nuclear radiation emergency to prevent radioactive iodine from being absorbed by the thyroid gland
  • ThyroSafe is a thyroid-blocking tablet used only during a nuclear radiation emergency, as directed by public officials
Important instructions
  • Iosat: take by mouth once every 24 hours only when directed by public officials; do not take more than 1 dose per day
  • Iosat tablets can be taken whole or crushed and mixed with milk, baby formula, water, orange juice, flat soda, or raspberry syrup
  • ThyroSafe tablets can be taken whole or crushed; crushed tablet can also be dissolved in water and mixed with low-fat milk, juice, flat soda, raspberry syrup, or infant formula to make a liquid dose
  • ThyroSafe: the prepared liquid mixture can be stored in the refrigerator for up to 7 days; discard any unused portion
Available strengths 2 strengths
14 FDA-listed product records

Capsule

By mouth
Available strengths 1 strength
1 FDA-listed product record

📊 Potassium Iodide across the U.S. market

How Potassium Iodide appears in the FDA’s National Drug Code Directory — including its dosage forms, strengths, brand names, manufacturers, and FDA-listed product records. These are directory records, not sales or prescription volume.

4
Dose forms
20
Manufacturers
7
Brand names
56
FDA-listed product records
1979
First marketed

FDA-listed product records by dose form (tablet variants merged) — FDA National Drug Code Directory. Record counts are not sales or prescription volume.

Also listed with the FDA, not a patient dose form: Crystal (4) · Powder (3) — bulk drug substance sold to compounders/manufacturers and multi-item kits. These aren’t counted in the dose-form total above.

Boiron32%
Anbex Inc.11%
Merck KGaA7%
Atlantic Biologicals Corp.5%
BTG International Inc.5%
Mission Pharmacal Company5%
Other makers34%

Share of FDA-listed product records by manufacturer — FDA National Drug Code Directory. Record counts are not sales or prescription volume.

📈 How widely Potassium Iodide is used

A general measure of how commonly Potassium Iodide is prescribed, based on Medicaid — one of the largest public drug programs. The figure below is prescriptions filled in Q1–Q4 2025, summed across every form and brand of the drug.

Think of this as a proxy for how widely Potassium Iodide is used, drawn from freely available public data. Medicaid is just one program — these numbers don’t include Medicare, other government coverage, or commercial and cash-pay prescriptions, so real-world use is higher than what’s shown here.

355
Medicaid prescriptions filled (Q1–Q4 2025)
$50,424 gross Medicaid reimbursement (before mandatory rebates — net cost is lower)

How commonly is Potassium Iodide prescribed? Of the 1,596 medications we measure, Potassium Iodide ranks #1,399 by Medicaid prescriptions — more than 12% of them.

Where Potassium Iodide ranks among the drugs we measure · Q1–Q4 2025 · neighbors ±5

Utilization by Potassium Iodide product

Pick a product to see its own Medicaid numbers. Each chip is one clinical product — a specific strength & dosage form as defined by RxNorm — with brand-name and generic versions combined.

potassium iodide 1000 MG/ML Oral Solution

355 Medicaid prescriptions (Q1–Q4 2025) 100% of Potassium Iodide prescriptions shown $50,424 gross reimbursement (before rebates) ≈ $142 per prescription (gross)

Summed across the 2 of 8 listed NDC products with Medicaid activity — every brand and generic of this exact strength & form. RxNorm 312541

Shares are of the Medicaid prescriptions shown here. Product grouping follows RxNorm (the National Library of Medicine’s drug terminology), so “one product” means one strength & dosage form regardless of manufacturer. Dollar figures are gross Medicaid reimbursement before mandatory rebates — rebates (often large, especially for brand-name drugs) are confidential, so actual net cost to Medicaid is lower than shown.

Source: Medicaid State Drug Utilization Data (CMS), aggregated by generic ingredient — summed across every NDC (all brands, strengths, salt forms and dosage forms) of Potassium Iodide, and across all states and both fee-for-service and managed-care claims. A general popularity signal; it excludes Medicare, commercial insurance and cash prescriptions, so it is not total U.S. use. Based on the 2 of 8 listed Potassium Iodide NDCs with Medicaid activity.

🔍 Compare Potassium Iodide products

A representative set of FDA-listed product records for Potassium Iodide — across manufacturers, strengths, and dosage forms, grouped by form with each product’s manufacturer and how the FDA approved it. The same medicine may be made and packaged by different companies, so a single drug can have many directory entries. (It’s also why a refill can look different — a new shape, color, or box — even though it contains the same medication.)

Showing 56 of 56 products — FDA National Drug Code Directory. See every product, package size and price: browse all 56 Potassium Iodide NDCs →

RxNorm Concept Web — From Ingredient to Every Form and Strength

This page starts with one ingredient concept (IN). The branches below show its dose-form concepts (SCDF), then the available clinical drug and strength concepts (SCD). Combination products remain separate concepts with their own pages.

Ingredient (IN) Potassium Iodide RxCUI 8597 3 dose forms · 4 strengths
  1. Dose form (SCDF) Delayed Release Oral Tablet RxCUI 373541 No current FDA listing
  2. Dose form (SCDF) Oral Solution RxCUI 373539 In current FDA listings
    Clinical drug / strength (SCD) 65 MG/ML RxCUI 242429 1000 MG/ML RxCUI 312541
  3. Dose form (SCDF) Oral Tablet RxCUI 375919 In current FDA listings
    Clinical drug / strength (SCD) 65 MG RxCUI 430174 130 MG RxCUI 312539

Look up RxCUI 8597 in the RxCUI Atlas →

RxNorm is the U.S. National Library of Medicine’s normalized drug vocabulary. Its concept hierarchy can include forms that are not currently marketed; the status on each branch compares that concept with current FDA listings. RxCUIs identify vocabulary concepts, not individual packages or manufacturers.

🏷️ Sold under these brand names

Iosat ThyroSafe ThyroShield SSKI brand of Potassium Iodide Kali iodatum Sski Kali Iodatum 1x

🏭 Manufacturers & labelers

Boiron 18 Anbex Inc. 6 Merck KGaA 4 Atlantic Biologicals Corp. 3 BTG International Inc. 3 Mission Pharmacal Company 3 Avondale Pharmaceuticals, LLC 2 BTG International Inc 2 Nivagen Pharmaceuticals, Inc. 2 Nature's Fusions, Llc 2 Natural Creations, Inc. 2 Washington Homeopathic Products 1 Recipharm AB (publ) 1 Professional Compounding Centers of America dba PCCA 1 Laser Pharmaceuticals Inc. 1 Eskay Iodine Pvt. Ltd. 1 Emerald Therapeutics, LLC 1 Deseret Laboratories, Inc. 1 Bryant Ranch Prepack 1 BGR Chemical Products Inc. 1

RxNorm drug class

Potassium Iodide belongs to the Expectorants class.

Drug family (ATC) Expectorants, Other ophthalmologicals, Antidotes

Classified by RxNorm RxClass — the U.S. National Library of Medicine's standardized drug-classification service (Established Pharmacologic Class from the FDA, the ATC drug family from the WHO, and mechanism of action). Reference only, not medical advice.

🔬 Where this comes from

Core label, product, RxNorm, safety, and utilization data on this page come from the sources identified below. AI-written, editorial, and licensed sections are labeled separately.

📄
FDA-filed drug labels (SPL) Uses, dosing, warnings & side effects from SPL records retrieved through openFDA; the linked representative set can be verified on DailyMed. ✓ Linked label effective Oct 3, 2025
🏭
Forms, brands & labelersAggregated from ingredient-matched FDA National Drug Code Directory product records for Potassium Iodide.
📈
Real-world reportsThe FDA Adverse Event Reporting System (FAERS), served through openFDA.
🚨
Recalls & shortagesopenFDA drug-enforcement reports and the FDA drug-shortage database.
🧾 Clinical label set — FDA-filed SPL labels retained for Potassium Iodide after exact ingredient or ingredient-combination matching and applicable route/form matching
Clinical labels in scope
10
NDC products indexed
56
Distinct labelers/manufacturers represented
20
Linked representative label
Anbex Inc.
Linked label effective
Oct 3, 2025
Composite sections available
19
Linked SPL Set ID
bab815ee-47ef-4c87-a60d-e0d7863ad871
Linked SPL Document ID
404359f0-cb48-bcf0-e063-6294a90a6191
Open the linked representative label on DailyMed ↗

How we combine label and product data

HelloPharmacist combines public FDA and NLM records; we don’t author the underlying clinical facts. We identified 10 FDA-filed SPL label sets within the page’s selected clinical scope after exact ingredient or ingredient-combination matching and applicable route/form matching. The representative label is the starting point for the displayed reference monograph; the 12 largest stored in-scope SPL records, which may include that representative, are compared section by section, and the longest available version of each section is retained. Forms, routes, brands, labelers, product-listed strengths, and product-record counts are aggregated separately from ingredient-matched FDA NDC Directory records; package records listed above are associated with the linked SPL; and the normalized concept hierarchy comes from NLM RxNorm.

For canonical ingredient pages, bounded product-attributed indication and administration excerpts may be added to the AI evidence, and the generator is instructed to preserve available product, brand, route, and form qualifiers instead of treating one label as universal. Where a section is identified as AI-written, its plain-language text is generated from bounded label evidence. New draft drug pages remain in the admin review queue before first publication. Anbex Inc. is the representative DailyMed label linked for verification and dates; it is not the sole source used for the page.

This is general education, not medical advice — always consult your doctor or pharmacist about your medications and any medical condition. For the exact wording of the linked representative label, view that label on DailyMed; some displayed composite sections may come from other in-scope SPL labels. Learn how we use AI and our data sources & update cadence.