There are many drugs that have the potential to induce hypothyroidism. Drug- induced hypothyroidism is an underactive thyroid gland due to a reaction to a medication. If your hypothyroid symptoms began after starting a medication, you may be suffering from drug-induced hypothyroidism. Here is a list of some medications known to cause hypothyroidism. For a detailed explanation of the mechanisms by which these drugs exert their influence on thyroid hormone, read: Drugs That Suppress TSH or Cause Central Hypothyroidism, Best Pract Res Clin Endocrinol Metab. 2009 Dec; 23(6) 793-800.
Drugs impact thyroid function at many different levels; from the hypothalamus to pituitary, synthesis and secretion by the thyroid gland, metabolism, binding of thyroid to its major binding protein, altering thyroid receptor function, and absorption of medication from the GI tract.
Drugs that affect thyroid function in normal patients:
Inhibition of T4/T3 synthesis
Propylthiouracil
Methimazole
Inhibition of T4/T3 secretion
Lithium
Iodide
Amiodarone
Aminoglutethimide
Thyroiditis
Interferon
Interleukin-2
Amiodarone
Sunitinib
Jod-Basedow Hyperthyroidism
Iodide
Amiodarone
TSH suppression
Glucocorticoids
Dopamine agonists
Somatostatin analogs
Rexinoids Carbemazepine/Oxcarbemazepine
Metformin
TSH elevation
Metyrapone
Displacement from thyroxine binding globulin (laboratory artifact)
Furosemide
Phenytoin
Probenecid
Heparin
Nonsteroidal anti-inflammatory medications
Drugs affecting patients taking levothyroxine:
Inhibition of levothyroxine absorption
Antacids (Tums, Rolaids, etc)
Antibiotics (Cipro, Maxaquin, Levaquin, Avelox, Norox-in, Floxin)
Aluminum hydroxide
Calcium
Colestyramine (Questran)
Colestipol
Iron and Iron Supplements
Sucralfate (Carafate)
Raloxifene (Evista)
Sevelamer (Renagel, Renvela)
Increased hepatic metabolism
Carbemazepine (Tegretol)
Phenobarbitol (Luminal, Solfoton)
Oxycarbazepine (Trileptal)
Phenytoin (Dilantin)
Primidone (Mysoline)
Rifampin TKI (Imatinib, axitinib, motesanib, vandetanib)
Rexinoids
St. John’s Wort
Decrease hepatic metabolism
Metformin
Inhibition of 5’ deiodinase
Propylthiouracil
Methimazole
Propranolol
Glucocorticoids
Iodide
Increased thyroxine binding globulin levels
Estrogen
Raloxifene
Tamoxifen
Methadone
Mitotane
Fluorouracil
Decreased thyroxine binding globulin levels
Androgens
Glucocorticoids
Nicotinic acid
Interactions with other drugs
Warfarin (Coumadin)- both low and high thyroid function can alter the blood-thinning response of Coumadin
Drugs toxic to the thyroid- Drugs containing bromide or fluoride can be toxic to the thyroid or can displace iodine as the central molecule in thyroid hormone
Advair (fluticasone)
Alphagen (brimonidine)
bromide Atrovent (Ipratropium)
bromide Avelox (moxifloxacin)
Adovart (dulasteride)
Celebrex (celecoxib)
Celexa (citalopram) both fluoride and bromide
Cipro (ciprofloxacin)
Clinoril (sulindac)
Combivent (from the ipratropium)bromide
Crestor (rosuvastatin)
Diflucan (fluconazole)
DuoNeb (nebulized Combivent)
Enablex (darifenacin)
bromide Flonase (fluticasone)
Flovent (fluticasone)
Guaifenex DM (dextromethorphan) bromide
Lescol (fluvastatin)
Levaquin (levofloxacin)
Lexapro (escitalopram)
Lipitor (atorvastatin)
Lotrisone topical cream Paxil (paroxetine)
Prevacid (lansoprazole)
Protonix (pantoprazole)
Prozac (fluoxetine)
Pulmicort (budesonide)
Razadyne (galantamine) bromide
Risperdal (risperidone)
Spiriva (tiotropium) bromide
Tobra Dex (from dexamethasone)
Travatan (travoprost)
Triamcinolone Vigamox (moxifloxacin)
Vytorin (from eztimibe)
Zetia (eztimibe)
Learn more about thyroid function and hypothyroidism on our website.
About the Author: Dr. Douglas L. Weed
Dr. Weed practices Functional Nutrition, Chiropractic care, and offers weight loss solutions in Napa, CA at Heun Chiropractic, Inc. He has a doctorate in Chiropractic care and he has received certifications in physical rehabilitation and as a Qualified Medical Examiner. With a post-graduate certification in Functional Medicine, focusing on functional endocrinology, digestive disorders and Peripheral Neuropathy, he is committed to lifelong education and helping patience transform their health.