From the Guidelines
No, fluoxetine is not prescribed for bradycardia. Fluoxetine is a selective serotonin reuptake inhibitor (SSRI) antidepressant primarily used to treat depression, obsessive-compulsive disorder, panic disorder, bulimia nervosa, and premenstrual dysphoric disorder. In fact, fluoxetine may occasionally cause cardiac side effects including palpitations and, rarely, may contribute to arrhythmias in some patients 1. Bradycardia, which is an abnormally slow heart rate (typically below 60 beats per minute), is typically treated with different approaches depending on the cause, including discontinuation of medications that slow heart rate, atropine in acute situations, or pacemaker implantation for chronic cases, as recommended by the 2018 ACC/AHA/HRS guideline on the evaluation and management of patients with bradycardia and cardiac conduction delay 1.
The treatment of bradycardia focuses on addressing the underlying cause or providing interventions that increase heart rate, while fluoxetine's mechanism of action affects neurotransmitters in the brain rather than directly influencing heart rate regulation. According to the guideline, first-line drug treatment for symptomatic bradycardia is atropine 0.5 to 1 mg IV repeated every 3 to 5 minutes as needed up to 1.5 to 3 mg total 1. If not effective, then consider epinephrine (2 to 10 µg/min) or dopamine (2 to 10 µg/kg/min).
Some key points to consider in the management of bradycardia include:
- Discontinuation of medications that slow heart rate
- Atropine in acute situations
- Pacemaker implantation for chronic cases
- Lifestyle interventions
- Pharmacotherapy
- External and implanted device-based therapies, with particular attention to indications for temporary and permanent pacing, as outlined in the 2018 ACC/AHA/HRS guideline 1.
Overall, fluoxetine is not a recommended treatment for bradycardia, and its use may even be contraindicated in certain cases due to its potential to cause cardiac side effects 1.
From the Research
Fluoxetine and Bradycardia
- Fluoxetine is not typically prescribed for bradycardia, as it can actually cause bradycardia as a side effect in some cases 2, 3, 4.
- Studies have reported cases of dysrhythmia, including bradycardia, associated with fluoxetine treatment 3, 4.
- The mechanism of bradycardia caused by fluoxetine is thought to be a direct central nervous system effect of increased serotonin on medullary cardiovascular regulation 4.
- Bradycardia is a commonly observed arrhythmia that can be caused by various factors, including pathology within the sinus node, atrioventricular nodal tissue, and the specialized His-Purkinje conduction system 5.
- Treatment for bradycardia should be based on a thorough evaluation of symptoms and disease states, rather than solely on heart rate or pause duration 5.
Cardiovascular Effects of Fluoxetine
- Fluoxetine has been shown to have cardiodepressant and vasodilatory effects in isolated heart preparations and vessels of rats and rabbits 2.
- The drug can cause a range of cardiovascular side effects, including dysrhythmia, orthostatic hypotension, and syncope 2, 3, 4.
- The risk of cardiovascular side effects may be increased in patients with preexisting heart disease and in the elderly 3, 6.
- Aging may increase plasma levels of fluoxetine, which could contribute to the development of cardiovascular side effects 6.