Drug Interaction Report

ADJUST DOSING INTERVAL: Certain drugs may affect the pharmacokinetics, pharmacodynamics, and/or diagnostic results of radioiodides.

MANAGEMENT: Antithyroid agents such as carbimazole or propylthiouracil should generally be withheld for 1 week before administration of sodium iodide I-131 or I-123, and for a few days afterward. Salicylates, steroids, anticoagulants, antihistamines, antiparasitics, penicillins, sulfonamides, tolbutamide, thiopental, and nitroprusside should generally be withheld for 1 week. Amiodarone, lithium, and benzodiazepines should be withheld for at least 4 weeks.

ADJUST DOSING INTERVAL: Certain penicillins may exhibit reduced gastrointestinal absorption in the presence of food. The therapeutic effect of the antimicrobial may be reduced.

MANAGEMENT: The interacting penicillin should be administered one hour before or two hours after meals. Penicillin V and amoxicillin are not affected by food and may be given without regard to meals.

MONITOR: Excessive intake of dietary iodine (e.g., iodised salt) may interfere with adequate uptake of radioiodide by the thyroid .

MANAGEMENT: A diet low in iodine is recommended before initiating therapy with sodium iodide I-131 or I-123.

ADJUST DOSING INTERVAL: Certain drugs may affect the pharmacokinetics, pharmacodynamics, and/or diagnostic results of radioiodides.

MANAGEMENT: Antithyroid agents such as carbimazole or propylthiouracil should generally be withheld for 1 week before administration of sodium iodide I-131 or I-123, and for a few days afterward. Salicylates, steroids, anticoagulants, antihistamines, antiparasitics, penicillins, sulfonamides, tolbutamide, thiopental, and nitroprusside should generally be withheld for 1 week. Amiodarone, lithium, and benzodiazepines should be withheld for at least 4 weeks.