Dosing & Uses
Dosage Forms & Strengths
tablet
- 65mg
- 130mg
oral solution
- 65mg/mL
- 325mg/5mL
oral solution (concentrated)
- 1g/mL
Radiation Emergency
Indicted during environmental radiation emergency to block uptake of radioactive iodine isotopes in thyroid and reduce risk of thyroid cancer
130 mg PO qDay; not to exceed 1 dose/24 hr
Ideally initiate 1-48 hr prior to exposure
Continue daily dose until exposure risk has passed and/or until other measures (eg, evacuation, sheltering, control of the food and milk supply) have been successfully implemented
Risk reduction with acute exposure
- KI initiated shortly before or immediately after acute exposure: 90-99% risk reduction
- KI initiated within 3-4 hr after acute exposure: 50% risk reduction
- KI initiated up to 12 hr after acute exposure: limited benefit may be achieved
Expectorant
SSKI: 300-600 mg PO q6-8hr
Thyrotoxic Crisis
250-500 mg (5-10 gtt of 1 g/mL) PO q4-6hr
Preoperative Thyroidectomy
50-250 mg (1-5 gtt of 1 g/mL) PO q8hr for 10-14 days
Other Indications & Uses
Cystic fibrosis, chronic sinusitis (adjunct)
Dosage Forms & Strengths
tablet
- 65mg
- 130mg
oral solution
- 65mg/mL
- 325mg/5mL
oral solution
- 1g/mL
Radiation Emergency
Indicted during environmental radiation emergency to block uptake of radioactive iodine isotopes in thyroid and reduce risk of thyroid cancer
Infants <1 month: 16.25 mg PO qDay; not to exceed 1 dose/24 hr
1 month-3 years: 32.5 mg PO qDay; not to exceed 1 dose/24 hr
3-13 years: 65 mg PO qDay; not to exceed 1 dose/24 hr
>13 years or adolescents weighing >70 kg (154 lb): 130 mg PO qDay; not to exceed 1 dose/24 hr
Ideally initiate 1-48 hr prior to exposure
Continue daily dose until exposure risk has passed and/or until other measures (eg, evacuation, sheltering, control of the food and milk supply) have been successfully implemented
Risk reduction with acute exposure
- KI initiated shortly before or immediately after acute exposure: 90-99% risk reduction
- KI initiated within 3-4 hr after acute exposure: 50% risk reduction
- KI initiated up to 12 hr after acute exposure: limited benefit may be achieved
Neonatal Graves Disease
SSKI: 1 gtt PO q8hr
Expectorant
SSKI: 60-250 mg PO q6hr
Interactions
Interaction Checker
No Results

Contraindicated
Serious - Use Alternative
Significant - Monitor Closely
Minor

Contraindicated (1)
- sodium iodide I-131
potassium iodide will decrease the level or effect of sodium iodide I-131 by Other (see comment). Contraindicated. Discontinue iodide-containing supplements at least 10 days before administering sodium iodide I-131 and do not coadminister; thyroid agents decrease uptake of sodium iodide I-131 by the thyroid gland.
Serious - Use Alternative (0)
Monitor Closely (54)
- amiloride
potassium iodide and amiloride both increase serum potassium. Use Caution/Monitor. Potassium salts may increase the hyperkalemic effects of potassium-sparing diuretics.
- aspirin
potassium iodide and aspirin both increase serum potassium. Use Caution/Monitor.
- aspirin rectal
potassium iodide and aspirin rectal both increase serum potassium. Use Caution/Monitor.
- azilsartan
potassium iodide and azilsartan both increase serum potassium. Use Caution/Monitor. Potassium salts may increase the hyperkalemic effects of ARBs; the effect may be the result of aldosterone suppression in patients receiving ARBs.
- benazepril
potassium iodide and benazepril both increase serum potassium. Use Caution/Monitor. Potassium salts may increase the hyperkalemic effects of ACE inhibitors; the effect may be the result of aldosterone suppression in patients receiving ACE inhibitors.
- candesartan
potassium iodide and candesartan both increase serum potassium. Use Caution/Monitor. Potassium salts may increase the hyperkalemic effects of ARBs; the effect may be the result of aldosterone suppression in patients receiving ARBs.
- captopril
potassium iodide and captopril both increase serum potassium. Use Caution/Monitor. Potassium salts may increase the hyperkalemic effects of ACE inhibitors; the effect may be the result of aldosterone suppression in patients receiving ACE inhibitors.
- celecoxib
potassium iodide and celecoxib both increase serum potassium. Use Caution/Monitor.
- choline magnesium trisalicylate
potassium iodide and choline magnesium trisalicylate both increase serum potassium. Use Caution/Monitor.
- diclofenac
potassium iodide and diclofenac both increase serum potassium. Use Caution/Monitor.
- diflunisal
potassium iodide and diflunisal both increase serum potassium. Use Caution/Monitor.
- drospirenone
potassium iodide and drospirenone both increase serum potassium. Use Caution/Monitor.
- enalapril
potassium iodide and enalapril both increase serum potassium. Use Caution/Monitor. Potassium salts may increase the hyperkalemic effects of ACE inhibitors; the effect may be the result of aldosterone suppression in patients receiving ACE inhibitors.
- eprosartan
potassium iodide and eprosartan both increase serum potassium. Use Caution/Monitor. Potassium salts may increase the hyperkalemic effects of ARBs; the effect may be the result of aldosterone suppression in patients receiving ARBs.
- etodolac
potassium iodide and etodolac both increase serum potassium. Use Caution/Monitor.
- fenoprofen
potassium iodide and fenoprofen both increase serum potassium. Use Caution/Monitor.
- flurbiprofen
potassium iodide and flurbiprofen both increase serum potassium. Use Caution/Monitor.
- fosinopril
potassium iodide and fosinopril both increase serum potassium. Use Caution/Monitor. Potassium salts may increase the hyperkalemic effects of ACE inhibitors; the effect may be the result of aldosterone suppression in patients receiving ACE inhibitors.
- ibuprofen
potassium iodide and ibuprofen both increase serum potassium. Use Caution/Monitor.
- ibuprofen IV
potassium iodide and ibuprofen IV both increase serum potassium. Use Caution/Monitor.
- ibuprofen/famotidine
potassium iodide and ibuprofen/famotidine both increase serum potassium. Use Caution/Monitor.
- indomethacin
potassium iodide and indomethacin both increase serum potassium. Use Caution/Monitor.
- iodine (radioactive)
potassium iodide, iodine (radioactive). Mechanism: pharmacodynamic synergism. Use Caution/Monitor. Concomitant use with antithyroid drugs may potentiate the hypothyroid and goitrogenic effects of potassium iodide.
- irbesartan
potassium iodide and irbesartan both increase serum potassium. Use Caution/Monitor. Potassium salts may increase the hyperkalemic effects of ARBs; the effect may be the result of aldosterone suppression in patients receiving ARBs.
- ketoprofen
potassium iodide and ketoprofen both increase serum potassium. Use Caution/Monitor.
- ketorolac
potassium iodide and ketorolac both increase serum potassium. Use Caution/Monitor.
- ketorolac intranasal
potassium iodide and ketorolac intranasal both increase serum potassium. Use Caution/Monitor.
- lisinopril
potassium iodide and lisinopril both increase serum potassium. Use Caution/Monitor. Potassium salts may increase the hyperkalemic effects of ACE inhibitors; the effect may be the result of aldosterone suppression in patients receiving ACE inhibitors.
- lithium
potassium iodide, lithium. Mechanism: pharmacodynamic synergism. Use Caution/Monitor. Concomitant use with antithyroid drugs may potentiate the hypothyroid and goitrogenic effects of potassium iodide.
- losartan
potassium iodide and losartan both increase serum potassium. Use Caution/Monitor. Potassium salts may increase the hyperkalemic effects of ARBs; the effect may be the result of aldosterone suppression in patients receiving ARBs.
- meclofenamate
potassium iodide and meclofenamate both increase serum potassium. Use Caution/Monitor.
- mefenamic acid
potassium iodide and mefenamic acid both increase serum potassium. Use Caution/Monitor.
- meloxicam
potassium iodide and meloxicam both increase serum potassium. Use Caution/Monitor.
- methimazole
potassium iodide, methimazole. Mechanism: pharmacodynamic synergism. Use Caution/Monitor. Concomitant use with antithyroid drugs may potentiate the hypothyroid and goitrogenic effects of potassium iodide.
- moexipril
potassium iodide and moexipril both increase serum potassium. Use Caution/Monitor. Potassium salts may increase the hyperkalemic effects of ACE inhibitors; the effect may be the result of aldosterone suppression in patients receiving ACE inhibitors.
- nabumetone
potassium iodide and nabumetone both increase serum potassium. Use Caution/Monitor.
- naproxen
potassium iodide and naproxen both increase serum potassium. Use Caution/Monitor.
- olmesartan
potassium iodide and olmesartan both increase serum potassium. Use Caution/Monitor. Potassium salts may increase the hyperkalemic effects of ARBs; the effect may be the result of aldosterone suppression in patients receiving ARBs.
- oxaprozin
potassium iodide and oxaprozin both increase serum potassium. Use Caution/Monitor.
- perindopril
potassium iodide and perindopril both increase serum potassium. Use Caution/Monitor. Potassium salts may increase the hyperkalemic effects of ACE inhibitors; the effect may be the result of aldosterone suppression in patients receiving ACE inhibitors.
- piroxicam
potassium iodide and piroxicam both increase serum potassium. Use Caution/Monitor.
- potassium citrate
potassium iodide and potassium citrate both increase serum potassium. Use Caution/Monitor.
- potassium phosphate
potassium iodide and potassium phosphate both increase serum potassium. Use Caution/Monitor.
- propylthiouracil
potassium iodide, propylthiouracil. Mechanism: pharmacodynamic synergism. Use Caution/Monitor. Concomitant use with antithyroid drugs may potentiate the hypothyroid and goitrogenic effects of potassium iodide.
- quinapril
potassium iodide and quinapril both increase serum potassium. Use Caution/Monitor. Potassium salts may increase the hyperkalemic effects of ACE inhibitors; the effect may be the result of aldosterone suppression in patients receiving ACE inhibitors.
- ramipril
potassium iodide and ramipril both increase serum potassium. Use Caution/Monitor. Potassium salts may increase the hyperkalemic effects of ACE inhibitors; the effect may be the result of aldosterone suppression in patients receiving ACE inhibitors.
- sacubitril/valsartan
potassium iodide and sacubitril/valsartan both increase serum potassium. Use Caution/Monitor. Potassium salts may increase the hyperkalemic effects of ARBs; the effect may be the result of aldosterone suppression in patients receiving ARBs.
- salsalate
potassium iodide and salsalate both increase serum potassium. Use Caution/Monitor.
- sulindac
potassium iodide and sulindac both increase serum potassium. Use Caution/Monitor.
- telmisartan
potassium iodide and telmisartan both increase serum potassium. Use Caution/Monitor. Potassium salts may increase the hyperkalemic effects of ARBs; the effect may be the result of aldosterone suppression in patients receiving ARBs.
- tolmetin
potassium iodide and tolmetin both increase serum potassium. Use Caution/Monitor.
- trandolapril
potassium iodide and trandolapril both increase serum potassium. Use Caution/Monitor. Potassium salts may increase the hyperkalemic effects of ACE inhibitors; the effect may be the result of aldosterone suppression in patients receiving ACE inhibitors.
- valsartan
potassium iodide and valsartan both increase serum potassium. Use Caution/Monitor. Potassium salts may increase the hyperkalemic effects of ARBs; the effect may be the result of aldosterone suppression in patients receiving ARBs.
- warfarin
potassium iodide decreases effects of warfarin by unspecified interaction mechanism. Use Caution/Monitor.
Minor (0)
Adverse Effects
Frequency Not Defined
Arrhythmia
Skin rash
Gastrointestinal irritation or bleeding
Diarrhea
Paresthesia
Swelling or neck or throat
Goiter
Hypothyroidism
Hyperthyroidism
Myxedema
Thyroid adenoma
Allergic reactions (fever, rash)
Lymph node swelling
Salivary gland swelling/tenderness
Warnings
Contraindications
Hypersensitivity; iodine sensitivity (although allergy to radiocontrast media, contact dermatitis from iodine-containing antibacterials, allergy to seafood should NOT be considered evidence of potassium iodide allergy)
Hyperthyroidism
Respiratory failure
Nodular thyroid disease with heart disease
Hypocomplementemic vasculitis
Dermatitis herpetiformis
Cautions
Avoid repeat dosing in neonates or women who are pregnant or breastfeeding if possible; in acute radiation exposure, prioritize these individuals for evacuation; although these precautions should be taken, the benefits of short-term use of KI to block uptake of radioactive iodine by the thyroid gland far exceed its chances of side effects
Prescribe for radiation exposure only upon order from authorities
Caution in tuberculosis
Iodine poisoning (Iodism) symptoms include metallic taste, sore mouth, severe headache
Iodine may cause allergic reaction, including shortness of breath or wheezing, skin rash, trouble breathing, speaking or swallowing, swelling, fever, and joint pain
Discontinue use and ask healthcare professional if experiencing an allergic reaction; get medical help right away if trouble breathing, speaking, or swallowing, swelling of the hands or feet, fever, or joint pain
If experiencing irregular heart or chest pain, get medical help right away
In case of overdose, get medical help or contact Poison Control Center right away
Pregnancy & Lactation
Pregnancy
Approved for use during nuclear radiation emergency to block thyroidal uptake of radioactive isotopes of iodine; initiate treatment immediately or during passage of radioactive cloud, but delayed administration is still beneficial
Repeated doses may suppress fetal thyroid function and are therefore not recommended; prioritize pregnant patients for evacuation from exposure area
If inadvertent exposure occurs, maternal potassium iodide may be administered to protect fetal thyroid; administer therapy within 12 hr of exposure but may not be necessary if mother <12 weeks pregnant
Lactation
Potassium iodide is present in milk; exposure to potassium iodide via breast milk may cause skin rash and thyroid suppression in breast infant
Therapy is approved for use during nuclear radiation emergency to block thyroidal uptake of radioactive isotopes or iodine
Pregnancy Categories
A: Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.
B: May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk. C: Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done. D: Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk. X: Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist. NA: Information not available.Pharmacology
Mechanism of Action
Expectorant: Iodine helps to increase respiratory secretions and decrease viscosity
Hyperthyroidism: Suppresses thyroid hormone synthesis
Thyroid protective: Systemically circulating potassium iodide is readily taken up by thyroid gland by sodium/iodide transporter in basal membrane; concentration gradient of thyroid gland to plasma is 20-50:1
Pharmacokinetics
Distribution: Significant extracellular distribution, with most accumulation in thyroid gland
Onset: Therapeutic effects in hyperthyroidism observed within 24 hr
Maximum effect: After 10-15 days of therapy
Duration of effect: Therapeutic effect may persist up to 6 weeks after chronic administration; 24 hr for radioactive iodine exposure
Metabolism: Unknown
Excretion: Renal
Images
Patient Handout
potassium iodide oral
POTASSIUM IODIDE - ORAL
(poh-TASS-ee-um EYE-oh-dyed)
COMMON BRAND NAME(S): SSKI
USES: Potassium iodide is used to loosen and break up mucus in the airways. This helps you cough up the mucus so you can breathe more easily if you have long-term lung problems (such as asthma, chronic bronchitis, emphysema). This medication is known as an expectorant.Potassium iodide is also used along with antithyroid medicines to prepare the thyroid gland for surgical removal, to treat certain overactive thyroid conditions (hyperthyroidism), and to protect the thyroid in a radiation exposure emergency. It works by shrinking the size of the thyroid gland and decreasing the amount of thyroid hormones produced.In a radiation emergency, potassium iodide blocks only the thyroid from absorbing radioactive iodine, protecting it from damage and reducing the risk of thyroid cancer. Use this medication along with other emergency measures that will be recommended to you by public health and safety officials (such as finding safe shelter, evacuation, controlling food supply).
HOW TO USE: Take this medication by mouth with a full glass of water (8 ounces or 240 milliliters) as directed by your doctor or public health and safety officials. To avoid stomach upset, take after meals or with food. Drink plenty of liquids with this medication unless otherwise directed. If you are taking the tablets, do not lie down for at least 10 minutes after taking this medication. If you are using the drops or liquid medication, use the dropper that comes with the bottle or a medication spoon/device to measure the correct dose. Liquid forms of this product may be mixed in water, milk, formula, or juice before taking. Do not use this medication if the solution turns brownish-yellow.Dosage is based on your medical condition and response to therapy. In children, dosage is also based on age. Do not increase your dose, take it more often, or take it for longer than prescribed or recommended because of the increased risk of side effects.In a radiation emergency, take this drug only when public health and safety officials tell you to do so. Read the Patient Information Leaflet that comes with the medication. Start treatment as soon as possible for the best protection. Take this medication usually once every 24 hours. The length of treatment will be determined by public health and safety officials and depends on several factors (such as whether you continue to be exposed to the radiation, and whether you are pregnant, breast-feeding, or have a newborn baby). See also Precautions.If so directed, use this medication regularly to get the most benefit from it. To help you remember, take it at the same time(s) each day.Tell your doctor if your condition lasts or gets worse.
SIDE EFFECTS: Nausea, vomiting, stomach ache, diarrhea, metallic taste in the mouth, fever, headache, or acne may occur. If any of these effects last or get worse, tell your doctor or pharmacist promptly.If your doctor has directed you to use this medication, remember that your doctor has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.Tell your doctor right away if you have any serious side effects, including: burning mouth/throat, sore teeth/gums, swelling inside the mouth, increased saliva, eye irritation/swollen eyelids, severe headache, swelling of the front of the neck/throat (goiter), signs of decreased thyroid gland function (such as weight gain, cold intolerance, slow/irregular heartbeat, constipation, unusual tiredness), confusion, numbness/tingling/pain/weakness of the hands/feet.Get medical help right away if you have any very serious side effects, including: chest pain, black stools, vomit that looks like coffee grounds, bloody diarrhea.A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing, fever with joint pain.This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.In the US -Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or at www.fda.gov/medwatch.In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.
PRECAUTIONS: Before taking potassium iodide, tell your doctor or pharmacist if you are allergic to it; or to iodine; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.Before using this medication, tell your doctor or pharmacist your medical history, especially of: current attack/worsening of bronchitis (if taking potassium iodide to thin mucus in the lungs), a certain type of skin condition (dermatitis herpetiformis), a certain type of blood vessel disease (hypocomplementemic vasculitis), certain thyroid disorders (such as multinodular goiter, Graves' disease, autoimmune thyroiditis, nodular thyroid disease with heart disease), overactive thyroid disease (unless you are specifically prescribed potassium iodide to treat hyperthyroidism), tuberculosis, high potassium blood level, kidney disease, Addison's disease, a certain muscle disorder (myotonia congenita).Caution is advised when this drug is given to newborn babies younger than 1 month old. Treatment for more than 1 day should be avoided because repeated dosing increases the risk of blocking thyroid function, possibly affecting the newborn's brain development. If treatment is needed for longer than 1 day, discuss the risks and benefits with the doctor. Treated babies should be given thyroid function tests.During pregnancy, this medication should be used only when clearly needed. Treatment for more than 1 day should be avoided because repeated dosing increases the risk of blocking thyroid function in the unborn baby, possibly causing harm. If treatment is needed for longer than 1 day, discuss the risks and benefits with your doctor.Caution is advised when this drug is used by women who are breast-feeding. This drug passes into breast milk. Treatment for more than 1 day should be avoided if you are breast-feeding because repeated dosing increases the risk of blocking thyroid function in the nursing infant. This effect may cause harm, especially in newborns younger than 1 month old. If treatment is needed for longer than 1 day, discuss with your doctor the risks and benefits, as well as whether you should stop breast-feeding.
DRUG INTERACTIONS: Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval.Some products that may interact with this drug are: ACE inhibitors (such as captopril, lisinopril), angiotensin receptor blockers (ARBs such as losartan, valsartan), certain "water pills" (potassium-sparing diuretics such as amiloride, spironolactone, triamterene), drospirenone, eplerenone, lithium, potassium-containing drugs (including supplements such as potassium chloride).
OVERDOSE: If someone has overdosed and has serious symptoms such as passing out or trouble breathing, call 911. Otherwise, call a poison control center right away. US residents can call their local poison control center at 1-800-222-1222. Canada residents can call a provincial poison control center.
NOTES: Do not share this medication with others.Lab and/or medical tests (such as thyroid function) should be done while you are taking this medication. Keep all medical and lab appointments. Consult your doctor for more details.
MISSED DOSE: If you miss a dose, take it as soon as you remember. If it is near the time of the next dose, skip the missed dose. Take your next dose at the regular time. Do not double the dose to catch up.
STORAGE: Store at room temperature away from light and moisture. Do not freeze. If crystals form in the solution, dissolve them by placing the closed bottle in a container of warm water, then gently shake the bottle. Do not store in the bathroom. Keep all medications away from children and pets.Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company.
Information last revised November 2022. Copyright(c) 2023 First Databank, Inc.
IMPORTANT: HOW TO USE THIS INFORMATION: This is a summary and does NOT have all possible information about this product. This information does not assure that this product is safe, effective, or appropriate for you. This information is not individual medical advice and does not substitute for the advice of your health care professional. Always ask your health care professional for complete information about this product and your specific health needs.
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