Lugol's (iodine/potassium iodide)

Iodine solution and tincture are applied topically to the affected areas as necessary; to avoid irritation, surfaces to which the preparations are applied should not be covered.

Potassium iodide is administered orally.

For use during a radiation emergency, potassium iodide is commercially available as tablets containing 65 or 130 mg of the drug and as an oral solution containing 65 mg/mL. If the oral solution containing 65 mg/mL is used, the dose should be administered undiluted using the calibrated dropper provided by the manufacturer.

For other indications, an oral solution of potassium iodide containing 1 g/mL (also known as saturated solution of potassium iodide (SSKI(R))) also is available. If this oral solution is used, the dose should be administered in a glassful of water, fruit juice, or milk. To minimize GI irritation, the dose should be taken with food or milk. A calibrated dropper marked to deliver 300 mg (0.3 mL) or 600 mg (0.6 mL) of the drug is provided by the manufacturer. If a dose of the oral solution containing 1 g/mL is administered using a standard medicinal dropper, each drop (0.05 mL) contains 50 mg of potassium iodide.

Potassium iodide may be available as strong iodine solution (also known as Lugol's solution), an oral solution containing 50 mg of iodine and 100 mg of potassium iodide per mL; this preparation may be commercially available but is not approved by the US Food and Drug Administration (FDA). Doses of strong iodine solution should be diluted in water or juice. If a dose of strong iodine solution is administered using a standard medicinal dropper, each drop contains 8 mg of iodide.

No dosing information is available for this tab.

No dosing information is available for this tab.

Concomitant use of lithium salts and iodides may result in additive or synergistic hypothyroid effects. Hypothyroidism has been reported in several patients who received the drugs concomitantly. A lithium salt and potassium iodide generally should not be used concomitantly; if the drugs are used together, the patient should be monitored closely for signs and symptoms of hypothyroidism.

Concomitant use of antithyroid agents (e.g., methimazole) and potassium iodide may result in additive hypothyroid and goitrogenic effects.

Concomitant use of potassium iodide and potassium-containing drugs, potassium-sparing diuretics, or angiotensin-converting enzyme (ACE) inhibitors may be associated with hyperkalemia, which may result in cardiac arrhythmias or cardiac arrest.

There are no contraindication interactions for this drug.

Severe Interaction: Action is required to reduce the risk of severe adverse interaction.

Agents That Affect Iodide/Radioactive Iodide

SEVERITY LEVEL: 2-Severe Interaction: Action is required to reduce the risk of severe adverse interaction.

MECHANISM OF ACTION: Many compounds can affect iodide protein binding and alter iodide pharmacokinetics and pharmacodynamics.(1)

CLINICAL EFFECTS: Compounds that affect iodide pharmacokinetics and pharmacodynamics may impact the effectiveness of radioactive iodide.(1)

PREDISPOSING FACTORS: Compounds that affect iodide pharmacokinetics and pharmacodynamics are expected to have the most impact during therapy using radioactive iodide. Diagnostic procedures would be expected to be impacted less.

PATIENT MANAGEMENT: Discuss the use of agents that affect iodide pharmacokinetics and pharmacodynamics with the patient's oncologist.(1) Because indocyanine green contains sodium iodide, the iodine-binding capacity of thyroid tissue may be reduced for at least one week following administration. Do not perform radioactive iodine uptake studies for at least one week following administration of indocyanine green.(2) The manufacturer of iopamidol states administration may interfere with thyroid uptake of radioactive iodine and decrease therapeutic and diagnostic efficacy. Avoid thyroid therapy or testing for up to 6 weeks post administration of iopamidol.(3)

DISCUSSION: Many agents interact with radioactive iodine. The average duration of effect is: anticoagulants - 1 week antihistamines - 1 week anti-thyroid drugs, e.g: carbimazole, methimazole, propylthiouracil - 3-5 days corticosteroids - 1 week iodide-containing medications, e.g: amiodarone - 1-6 months expectorants - 2 weeks Lugol solution - 3 weeks saturated solution of potassium iodine - 3 weeks vitamins - 10-14 days iodide-containing X-ray contrast agents - up to 1 year lithium - 4 weeks phenylbutazone - 1-2 weeks sulfonamides - 1 week thyroid hormones (natural or synthetic), e.g.: thyroxine - 4 weeks tri-iodothyronine - 2 weeks tolbutamide - 1 week topical iodide - 1-9 months (1)

Agents That Affect Iodide/Sodium Iodide I 131

SEVERITY LEVEL: 2-Severe Interaction: Action is required to reduce the risk of severe adverse interaction.

MECHANISM OF ACTION: Many compounds can affect iodide protein binding and alter iodide pharmacokinetics and pharmacodynamics.(1,2)

CLINICAL EFFECTS: Compounds that affect iodide pharmacokinetics and pharmacodynamics may impact the effectiveness of radioactive iodide.(1,2)

PREDISPOSING FACTORS: Compounds that affect iodide pharmacokinetics and pharmacodynamics are expected to have the most impact during therapy using radioactive iodide. Diagnostic procedures would be expected to be impacted less.

PATIENT MANAGEMENT: Discuss the use of agents that affect iodide pharmacokinetics and pharmacodynamics with the patient's oncologist.(1,2) Because indocyanine green contains sodium iodide, the iodine-binding capacity of thyroid tissue may be reduced for at least one week following administration. Do not perform radioactive iodine uptake studies for at least one week following administration of indocyanine green.(3) The manufacturer of iopamidol states administration may interfere with thyroid uptake of radioactive iodine and decrease therapeutic and diagnostic efficacy. Avoid thyroid therapy or testing for up to 6 weeks post administration of iopamidol.(4)

DISCUSSION: Many agents interact with radioactive iodine. The average duration of effect is: anticoagulants - 1 week antihistamines - 1 week anti-thyroid drugs, e.g: carbimazole, methimazole, propylthiouracil - 3-5 days corticosteroids - 1 week iodide-containing medications, e.g: amiodarone - 1-6 months expectorants - 2 weeks Lugol solution - 3 weeks saturated solution of potassium iodine - 3 weeks vitamins - 10-14 days iodide-containing X-ray contrast agents - up to 1 year lithium - 4 weeks phenylbutazone - 1-2 weeks sulfonamides - 1 week thyroid hormones (natural or synthetic), e.g.: thyroxine - 4 weeks tri-iodothyronine - 2 weeks tolbutamide - 1 week topical iodide - 1-9 months (1,2)

There are no moderate interactions for this drug.

There is no enhanced messaging for this drug.

• Pregnancy

There are no severe contraindications for this drug.

There are no moderate contraindications for this drug.

There is no enhanced messaging for this drug.

Rare or Very Rare

• Dermatitis due to topical drug

There are no less severe adverse reactions for this drug.

No enhanced messaging available.

No enhanced messaging available.

Iodides readily cross the placenta and may result in abnormal thyroid function and/or goiter in the neonate. Fetal thyroid may be most susceptible to the effects of excess iodine at the end of gestation.

Some experts state that potassium iodide is contraindicated in pregnant women. The American Academy of Pediatrics (AAP) states that use of potassium iodide as an expectorant is contraindicated during pregnancy.

There is no evidence that short-term use (e.g., 10 days) of potassium iodide for preoperative management of hyperthyroidism in pregnant women with Graves' disease undergoing thyroidectomy+ is harmful to the fetus. If thyroidectomy is necessary for the treatment of hyperthyroidism during pregnancy, the American Thyroid Association (ATA) and American Association of Clinical Endocrinologists (AACE) recommend that the surgery be performed during the second trimester.

The FDA recommends that pregnant women receive potassium iodide during a radiation emergency for their own protection and that of the fetus; however, repeat administration should be avoided during pregnancy, unless other protective measures are not available. When repeat administration is indicated in a pregnant woman, consultation with a clinician is recommended and thyroid function monitoring may be indicated in the neonate.

If potassium iodide is used during pregnancy or if the patient becomes pregnant while receiving the drug, the patient should be informed of the potential risks to the fetus.

Potassium iodide is distributed into milk and may cause rash and thyroid suppression in nursing infants.

The AAP considers potassium iodide to be compatible with breast-feeding.

In a radiation emergency, the FDA recommends that lactating women receive potassium iodide for their own protection. However, repeat administration should be avoided in lactating women unless other protective measures are not available. If repeat administration is indicated in a nursing woman, consultation with a clinician is recommended; thyroid function monitoring may be indicated in a breast-fed neonate.

Because radioactive iodine is distributed into milk, some experts (including the AAP) recommend that lactating women temporarily not breast-feed after a radiation emergency, unless no alternative is available. Breast-feeding can then be resumed when public authorities declare it safe to do so. The fact that administration of potassium iodide to lactating women potentially can reduce the radioiodine content of milk should be considered.

No enhanced messaging available.