Is sertraline (Zoloft) associated with bradycardia?

From the Guidelines

Zoloft (sertraline) can potentially cause bradycardia as a side effect, though it's relatively uncommon, and if you're experiencing bradycardia while taking Zoloft, you should contact your healthcare provider promptly to adjust your treatment plan and prevent potential complications. If you're experiencing bradycardia (abnormally slow heart rate below 60 beats per minute) while taking Zoloft, do not stop taking Zoloft suddenly without medical guidance. Your doctor may need to adjust your dosage, switch you to a different antidepressant, or monitor your heart function more closely. The risk of bradycardia is higher in elderly patients, those with pre-existing heart conditions, or patients taking other medications that affect heart rate, as noted in the study 1. Zoloft affects serotonin levels in the brain, but it can also influence cardiac function through various mechanisms including autonomic nervous system modulation. Some patients may need an electrocardiogram (ECG) to assess cardiac function if bradycardia develops. While most cases of SSRI-related bradycardia are mild, severe cases can lead to dizziness, fatigue, fainting, or other complications, so medical evaluation is important if you notice a consistently slow heart rate. In the event of symptomatic bradycardia, atropine remains the first-line drug, as recommended in the 2010 American Heart Association guidelines for cardiopulmonary resuscitation and emergency cardiovascular care 1. Key considerations for managing bradycardia in patients taking Zoloft include:

• Monitoring heart rate and adjusting medication as needed
• Avoiding sudden discontinuation of Zoloft
• Considering alternative antidepressants if bradycardia persists
• Evaluating for underlying heart conditions or other medications that may contribute to bradycardia. It's essential to work closely with your healthcare provider to manage bradycardia and adjust your treatment plan to minimize risks and optimize outcomes, as emphasized in the clinical practice guideline for the assessment and treatment of children and adolescents with anxiety disorders 1.

From the FDA Drug Label

Sertraline administered in a flexible dose range of 50 to 200 mg/day (mean dose of 89 mg/day) was evaluated in a post-marketing, placebo-controlled trial of 372 randomized subjects with a DSM-IV diagnosis of major depressive disorder and recent history of myocardial infarction or unstable angina requiring hospitalization Exclusions from this trial included, among others, patients with uncontrolled hypertension, need for cardiac surgery, history of CABG within 3 months of index event, severe or symptomatic bradycardia, non-atherosclerotic cause of angina, clinically significant renal impairment (creatinine >2. 5 mg/dL), and clinically significant hepatic dysfunction Sertraline treatment initiated during the acute phase of recovery (within 30 days post-MI or post-hospitalization for unstable angina) was indistinguishable from placebo in this study on the following week 16 treatment endpoints: left ventricular ejection fraction, total cardiovascular events (angina, chest pain, edema, palpitations, syncope, postural dizziness, CHF, MI, tachycardia, bradycardia, and changes in BP), and major cardiovascular events involving death or requiring hospitalization (for MI, CHF, stroke, or angina). Other important adverse events reported with sertraline hydrochloride overdose (single or multiple drugs) include bradycardia, bundle branch block, coma, convulsions, delirium, hallucinations, hypertension, hypotension, manic reaction, pancreatitis, QT-interval prolongation, serotonin syndrome, stupor, syncope and Torsade de Pointes

Bradycardia and Zoloft:

• The FDA drug label for Zoloft (sertraline) mentions that severe or symptomatic bradycardia was an exclusion criterion in a post-marketing trial of patients with a recent history of myocardial infarction or unstable angina.
• The label also notes that bradycardia was reported as an adverse event in cases of sertraline overdose.
• However, the label does not provide direct evidence of a causal relationship between Zoloft and bradycardia in the general patient population.
• Patients with a history of heart disease or concomitant illnesses should be treated with caution when taking Zoloft, as the drug may affect hemodynamic responses 2, 2.
• In cases of overdose, bradycardia was reported as one of the adverse events, highlighting the need for careful monitoring and management of patients taking Zoloft 2.

From the Research

Zoloft and Bradycardia

• Zoloft, also known as sertraline, is a selective serotonin reuptake inhibitor (SSRI) used to treat depression and other mental health conditions.
• Bradycardia, or a slow heart rate, can be a symptom of various conditions, including those related to the heart or as a side effect of certain medications.
• According to the study 3, sertraline was found to have a lower heart rate variability (HRV) compared to non-users, but the association with heart rate (HR) was less robust.
• Another study 4 found that sertraline appears to be safe to use after myocardial infarction (MI) and may even improve mortality.
• However, there is no direct evidence in the provided studies that specifically links Zoloft to bradycardia as a common side effect.
• The study 5 discusses the management of bradycardia, emphasizing the importance of identifying underlying causes and using pharmacologic therapy and/or pacing to manage unstable or symptomatic bradyarrhythmias, but does not mention Zoloft or sertraline specifically.
• Other studies 6, 7 discuss the safety and efficacy of SSRIs, including sertraline, but do not provide direct evidence of a link between Zoloft and bradycardia.