Drugs That May Affect Thyroid Uptake - Causes Decreased Radiopharmaceutical Uptake

Adrenocorticosteroids

Meprobamate

Aminosalicylic acid

Morphine

Androgens

Oral cholecystographic agents

Anticoagulants
(Coumadin;
crystalline warfarin sodium, Du Pont,     Wilmington, DE;
Heparin)

Para-aminosalicylic acid

Perchlorates

Phenylbutazome

Proloid

Propylthiouracil

Resorcinol

Antihistamines

SSKI

Antitussives

Salicylates

Benzodiazepines

Sodium diatrizoate

Cimetidine

Sodium nitroprusside

Clioquinol

Sulfonamides

Competing anions
(Br-, SLO-4, BF-4, SCN-, TcO-4)

Sulfonylureas

Synthroid

Tapazole

Corticotrophin

Thiamazole

Cytomel

Thiocyanates

Diiodohydroxyquin

Thiopental

Dilantin

Thyroid extracts

Epinephrine

Thyrolar

Euthyroid

Thyroxine

Expectorants (iodine containing)

Tolbutamide

Topical iodides

Fluorides

Vitamins/mineral supplements

Iodides

Antithyroid drugs

Estrogens Iodinated
Radiopaque contrast media

Estrogens

Lithium

Iodine Tincture

Rebound following suppression with thyroid or antithyroid drugs

Iodine containing collyrium

Lugol’s solution

Recovery from iodinated contrast media

Meglumine

Sulfobromophthalein