Related Experiment Video
Updated: Dec 12, 2025
06:15
Zebra II as A Novel System to Record Electrophysiological Signals in Zebrafish
Published on: August 16, 2024
682
Thyroid effects of amiodarone: clinical update
Poorani N Goundan1, Stephanie L Lee
1Section of Endocrinology, Diabetes and Nutrition, Boston University School of Medicine, Boston Medical Center, Boston, Massachusetts, USA.
Current Opinion in Endocrinology, Diabetes, and Obesity
|August 11, 2020
Summary
Amiodarone can cause thyroid dysfunction, with significant changes in children appearing within two weeks. New research explores diagnosis, management, and treatment options for amiodarone-induced thyroid dysfunction.
Area of Science:
- Endocrinology
- Pharmacology
Background:
- Amiodarone is a widely used antiarrhythmic drug.
- Amiodarone is known to cause thyroid dysfunction, presenting diagnostic and management challenges.
Purpose of the Study:
- To review recent evidence on amiodarone's effects on the thyroid gland and thyroid function.
- To discuss recent findings in the diagnosis and management of amiodarone-induced thyroid dysfunction.
Main Methods:
- Literature review of recent publications.
- Analysis of retrospective studies and small clinical investigations.
Main Results:
- Clinically significant thyroid changes in children can occur within 2 weeks of amiodarone initiation.
- Beta-glucuronidase activity may differentiate amiodarone-induced thyrotoxicosis (AIT) types.
- Agranulocytosis incidence may be higher in AIT patients on thionamides.
- Steroid therapy shows potential for refractory AIT.
- Surgery may offer mortality benefits over medical therapy for AIT in heart failure patients.
Conclusions:
- Amiodarone-induced thyroid dysfunction requires careful monitoring, especially in pediatric populations.
- Emerging data suggest novel diagnostic markers and therapeutic strategies for AIT.
- Further controlled trials are needed to validate new treatment approaches for amiodarone-induced thyroid dysfunction.
More Related Videos
Related Concept Videos
01:12Antiarrhythmic Drugs: Class III Agents as Potassium Channel Blockers
1.7K
Class III antiarrhythmic drugs are a group of medications that can prolong action potentials in the heart. They achieve this by blocking potassium channels or enhancing inward currents from sodium channels. However, these drugs have a unique property of "reverse use-dependence," which is most pronounced at slower heart rates and can lead to torsades de pointes—a specific type of arrhythmia. However, it is essential to note that excessive QT interval prolongation—a measure of...
1.7K
01:22Antiarrhythmic Drugs: Class I Agents as Sodium Channel Blockers
2.5K
Class I antiarrhythmic drugs are used to treat various types of arrhythmias or irregular heart rhythms. These drugs block the sodium (Na+) channels in the cardiac cells, thereby affecting the movement of electrical impulses across the heart. Class I antiarrhythmic drugs are divided into three subgroups: Class IA, Class IB, and Class IC, each with distinct mechanisms of action and effects on the heart.
Class 1A Antiarrhythmic Drugs: These drugs work by moderately blocking sodium channels,...
Class 1A Antiarrhythmic Drugs: These drugs work by moderately blocking sodium channels,...
2.5K
01:26Heart Failure Drugs: Inotropic Agents
1.1K
Positive inotropic agents are commonly used as the first line of treatment for heart failure. One such agent is digoxin, derived from the genus Digitalis, which has been known for centuries but effectively utilized since 1785. However, these cardiac glycosides can have potentially toxic effects due to their mechanism of action, which involves inhibiting Na+/K+-ATPase and increasing contractility. Digoxin is absorbed orally and distributed in various tissues, including the CNS. It has a long...
1.1K
01:24Antiarrhythmic Drugs: Class II Agents as β-Adrenergic Blockers
1.2K
Adrenergic stimulation generally impacts cardiac rate and rhythm. Specifically, stimulation of the β-adrenoceptors triggers an increase in intracellular calcium ion influx and pacemaker currents, which may cause arrhythmias. Catecholamines like adrenaline also demonstrate β2-adrenoceptor-mediated hypokalemia, impacting cardiac action potential and disrupting the normal cardiac rhythm. Class II antiarrhythmic drugs are β-adrenoceptor antagonists or β-blockers, which...
1.2K
01:20Antiarrhythmic Drugs: Class IV Agents as Calcium Channel Blockers
1.4K
Class IV antiarrhythmic drugs, such as verapamil and diltiazem, block calcium channels. They primarily affect the heart, slowing the conduction in calcium-dependent tissues like the SA and AV nodes. These drugs manage reentrant supraventricular tachycardia (SVT) and reduce ventricular rate in atrial flutter/fibrillation.
Verapamil, a calcium channel blocker, inhibits calcium movement across myocardial cell membranes and vascular smooth muscle. This results in the dilation of coronary and...
Verapamil, a calcium channel blocker, inhibits calcium movement across myocardial cell membranes and vascular smooth muscle. This results in the dilation of coronary and...
1.4K
01:20Synthesis and Regulation of Thyroid Hormones
6.7K
Low blood levels of the thyroid hormones — triiodothyronine (T3) and thyroxine (T4) — signal the hypothalamus to release the thyrotropin-releasing hormone (TRH). TRH then reaches the pituitary gland and stimulates the release of thyroid-stimulating hormone(TSH) into the bloodstream.
Upon reaching the thyroid gland, TSH stimulates the follicular cells' active uptake of iodide ions from the blood. The ions diffuse to the apical surface of the cells and are oxidized to iodine. The...
Upon reaching the thyroid gland, TSH stimulates the follicular cells' active uptake of iodide ions from the blood. The ions diffuse to the apical surface of the cells and are oxidized to iodine. The...
6.7K