For tremors caused by amiodarone, what can be done to treat or reduce the tremors besides stopping the medication?

Comment by InpharmD Researcher

For management of amiodarone-induced tremors, aside from down-titration or discontinuing therapy, clinical literature describes use of propranolol or levetiracetam for symptomatic treatment; however, use of these agents has only been documented in singular case reports.

Background

A 2022 review article elaborates on the phenomenon of drug-induced tremor, focusing on its clinical features, diagnostic approaches, and management strategies. The review underscores that the diagnosis of drug-induced tremor can be complex due to its potential exacerbation of underlying tremors and the need for thorough evaluation, including reviewing a patient's medication history and considering possibilities like drug-induced Parkinsonism. Management generally involves discontinuation of the causative drug, which often resolves the tremor, though persistence can occur in some cases. Specifically for amiodarone-induced tremor, the review recommends evaluating for concomitant hyperthyroidism, reducing the dose to 200 mg daily if possible, and considering a β-adrenergic antagonist. The article also discusses the significance of identifying risk factors for drug-induced tremor, such as older age, male gender, and polypharmacy. It notes that distinguishing features such as sudden onset or task-specific tremors can aid in differentiating drug-induced tremors from other types. [1]

According to a 2005 review, amiodarone, a class III antiarrhythmic, is frequently associated with the induction of postural and intentional tremors, which resemble essential tremor. The tremors typically manifest in the 6–10 Hz range and can arise at any point during treatment, though they are dose-dependent and generally improve within two weeks following a reduction in dose or discontinuation of the medication. The maintenance of amiodarone at 200 mg daily reportedly balances effective arrhythmia control with minimal side effects. Although the precise mechanism underlying amiodarone-induced tremor remains undefined, amiodarone's capacity to induce hypo- or hyperthyroidism necessitates the exclusion of hyperthyroidism as a potential underlying cause for tremors in patients undergoing amiodarone therapy. The review emphasizes the significance of propranolol as a symptomatic treatment option, noting its efficacy in reducing tremor intensity in patients who continue to experience tremors despite dose adjustment. This highlights the importance of comprehensive monitoring and individualized treatment strategies to optimize patient outcomes while minimizing the impact of drug-induced tremor on daily life and functioning. [2]

Literature Review

A search of the published medical literature revealed 1 study investigating the researchable question:

For tremors caused by amiodarone, what can be done to treat or reduce the tremors besides stopping the medication?

Level of evidence

D - Case reports or unreliable data  Read more→


Please see Table 1 for your response.

 

Amiodarone-induced muscle tremor in an elderly patient: A case report

Design

 Case report

Case presentation

A 2022 case report detailed a rare adverse reaction of muscle tremors induced by amiodarone in an elderly patient. The report described an 84-year-old female who developed bilateral gastrocnemius tremors following the administration of amiodarone for paroxysmal supraventricular tachycardia and ventricular tachycardia. Despite the use of amiodarone, which is a Class III antiarrhythmic agent, the woman did not convert to sinus rhythm, and she experienced persistent frequent ventricular premature beats. Subsequently, she developed severe muscle tremors and pain, which were hypothesized to be drug-induced, particularly given that her symptoms emerged after intravenous amiodarone. No significant abnormalities were detected in auxiliary examinations, such as lumbar MRI or electromyography, which suggested the presence of bundle fibrillation potentials.

Upon discontinuation of amiodarone and an adjustment in her treatment regimen, introducing propafenone and levetiracetam 250 mg twice daily, the patient's symptoms gradually improved. The case report emphasized that while neuromyopathy is a known rare side effect of amiodarone, with an incidence between 3% and 30%, the occurrence of muscle tremors is particularly uncommon.

Study Author Conclusions

A case of lower limb muscle tremors caused by amiodarone was introduced, which was improved after treatment. When elderly patients receive amiodarone, cardiologists and pharmacists should carefully evaluate the long-term and short-term side effects, as well as whether the combined use with other drugs will increase the adverse reactions of amiodarone. Changes in the patient's condition should be closely observed, and if there are signs of adverse reactions, immediate intervention (e.g., changing the drug or reducing the dose of the drug) should be performed to reduce the adverse reactions of amiodarone.
References:

Zhu XY, Tang XH, Yu H. Amiodarone-induced muscle tremor in an elderly patient: A case report. World J Clin Cases. 2022;10(34):12726-12733. doi:10.12998/wjcc.v10.i34.12726