Medications and Thyroid Function
OVERVIEW
Many medications have effects on thyroid function, through multiple mechanisms:
- altered TSH secretion from the pituitary gland
- altered thyroid hormone secretion from the thyroid gland
- altered T3 and T4 transport in the serum
- altered T3 and T4 metabolism peripherally
- immune reconstitution
- tyrosine kinase inhibtion
EXAMPLES
Alter TSH secretion from the pituitary gland
- Increase TSH: opioids
- Inhibits TSH release: glucocorticoids, dopamine, octreotide
- Bexarotene suppresses pituitary TSH-β promoter
Alter thyroid hormone secretion from the thyroid gland
- Decrease thyroid hormone synthesis: propylthiouracil, methimazole
- Decrease thyroid hormone secretion: iodide (Wolff-Chaikoff effect occurs over 7-10 days), amiodarone, lithium, Lugol’s solution
- Increase thyroid hormone secretion: iodide (escape from the Wolff-Chaikoff effect or the Jod-Basedow phenomenon occurs long-term), amiodarone
Decreased exogenous T4 absorption from the GI tract
- Cholesystramine, colestipol, sucralfate, ferrous sulfate, aluminum hydroxide, omeprazole
Alter T4 and T3 transport in serum
- Increase serum TBG: estrogens, heroin, methadone, mitotane, fluorouracil
- Decrease serum TBG: androgens, anabolic steroids
- Displacement from protein-binding sites: furosemide, salicylates, phenytoin, carbamazepine, meclofenamate, heparin
Alter T4 and T3 metabolism peripherally
- Increase hepatic metabolism: phenobarbital, phenytoin, carbamazepine and rifampin
- 5’-monodeiodinase inhibition (blocks metabolism of T4 to T3): glucocorticoids, propanolol, propylthiouracil, amiodarone, cytokines (e.g. IFN alpha)
Immune reconstitution
- Alemtuzumab
Hypothyroidism (tyrosine kinase inhibitors)
- Sunitinib: ? destructive thyroiditis,? blockade of iodine uptake,? inhibition of peroxidase activity
- Imatinib: ? induction of uridine diphosphate-glucuronosylotransferases (UGTs)
References and Links
CCC Pharmacology Series
Respiratory: Bosentan, Delivery of B2 Agonists in Intubated Patients, Nitric Oxide, Oxygen, Prostacyclin, Sildenafil
Cardiovascular: Adenosine, Adrenaline (Epinephrine), Amiodarone, Classification of Vasoactive drugs, Clevidipine, Digoxin, Dobutamine, Dopamine, Levosimendan, Levosimendan vs Dobutamine, Milrinone, Noradrenaline, Phenylephrine, Sodium Nitroprusside (SNiP), Sotalol, Vasopressin
Neurological: Dexmedetomidine, Ketamine, Levetiracetam, Lignocaine, Lithium, Midazolam, Physostigmine, Propofol, Sodium Valproate, Sugammadex, Thiopentone
Endocrine: Desmopressin, Glucagon Therapy, Medications and Thyroid Function
Gastrointestinal: Octreotide, Omeprazole, Ranitidine, Sucralfate, Terlipressin
Genitourinary: Furosemide, Mannitol, Spironolactone
Haematological: Activated Protein C, Alteplase, Aprotinin, Aspirin, Clopidogrel, Dipyridamole, DOACs, Factor VIIa, Heparin, LMW Heparin, Protamine, Prothrombinex, Tenecteplase, Tirofiban, Tranexamic Acid (TXA), Warfarin
Antimicrobial: Antimicrobial Dosing and Kill Characteristics, Benzylpenicillin, Ceftriaxone, Ciprofloxacin, Co-trimoxazole / Bactrim, Fluconazole, Gentamicin, Imipenem, Linezolid, Meropenem, Piperacillin-Tazobactam, Rifampicin, Vancomycin
Analgesic: Alfentanil, Celecoxib, COX II Inhibitors, Ketamine, Lignocaine, Morphine, NSAIDs, Opioids, Paracetamol (Acetaminophen), Paracetamol in Critical Illness, Tramadol
Miscellaneous: Activated Charcoal, Adverse Drug Reactions, Alkali Therapies, Drug Absorption in Critical Illness, Drug Infusion Doses, Epidural Complications, Epidural vs Opioids in Rib Fractures, Magnesium, Methylene Blue, Pharmacology and Critical Illness, PK and Obesity, PK and ECMO, Sodium Bicarbonate Use, Statins in Critical Illness, Therapeutic Drug Monitoring, Weights in Pharmacology
Toxicology: Digibind, Flumazenil, Glucagon Therapy, Intralipid, N-Acetylcysteine, Naloxone, Propofol Infusion Syndrome
- Kundra P, Burman KD. The effect of medications on thyroid function tests. Med Clin North Am. 2012 Mar;96(2):283-95. PMID: 22443976.
Critical Care
Compendium
Chris is an Intensivist and ECMO specialist at The Alfred ICU, where he is Deputy Director (Education). He is a Clinical Adjunct Associate Professor at Monash University, the Lead for the Clinician Educator Incubator programme, and a CICM First Part Examiner.
He is an internationally recognised Clinician Educator with a passion for helping clinicians learn and for improving the clinical performance of individuals and collectives. He was one of the founders of the FOAM movement (Free Open-Access Medical education) has been recognised for his contributions to education with awards from ANZICS, ANZAHPE, and ACEM.
His one great achievement is being the father of three amazing children.
On Bluesky, he is @precordialthump.bsky.social and on the site that Elon has screwed up, he is @precordialthump.
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