Why is dicyclomine (anticholinergic medication) contraindicated in heart failure and atrial fibrillation?

From the Guidelines

Dicyclomine is contraindicated in patients with heart failure and atrial fibrillation due to its anticholinergic properties, which can worsen these cardiac conditions by increasing heart rate and potentially exacerbating existing arrhythmias. As an anticholinergic medication, dicyclomine blocks muscarinic receptors, leading to tachycardia, which can place additional strain on an already compromised heart, potentially worsening cardiac output and exacerbating heart failure symptoms 1. The 2022 AHA/ACC/HFSA guideline for the management of heart failure emphasizes the importance of individualized strategies for rate or rhythm control in patients with heart failure and atrial fibrillation, but does not recommend the use of anticholinergic medications like dicyclomine 1.

Key Considerations

• Dicyclomine can cause urinary retention and constipation, leading to increased abdominal pressure and fluid retention, further complicating heart failure management.
• Alternative medications with fewer cardiovascular effects, such as peppermint oil, certain antispasmodics with less anticholinergic activity, or low-dose antidepressants that help with visceral pain, should be considered for patients with heart failure and atrial fibrillation who need treatment for irritable bowel syndrome or intestinal spasms.
• The European Society of Cardiology guidelines for the management of atrial fibrillation recommend the use of beta-blockers or non-dihydropyridine calcium channel blockers for heart rate control, but do not mention the use of anticholinergic medications like dicyclomine 1.

Clinical Implications

• Patients with heart failure and atrial fibrillation should be closely monitored for signs of worsening cardiac function when using any medication that may exacerbate their condition.
• Consultation with a cardiologist is recommended before using dicyclomine in patients with any cardiac condition.
• The potential benefits of using dicyclomine in patients with heart failure and atrial fibrillation do not outweigh the potential risks, and alternative treatments should be considered.

From the FDA Drug Label

Dicyclomine hydrochloride needs to be used with caution in conditions characterized by tachyarrhythmia such as thyrotoxicosis, congestive heart failure and in cardiac surgery, where they may further accelerate the heart rate. Care is required in patients with coronary heart disease, as ischemia and infarction may be worsened, and in patients with hypertension

Dicyclomine is bad in heart failure and atrial fibrillations because it may further accelerate the heart rate in conditions characterized by tachyarrhythmia, such as congestive heart failure. Additionally, care is required in patients with coronary heart disease, as dicyclomine may worsen ischemia and infarction. Key points to consider:

• Tachyarrhythmia: Dicyclomine may exacerbate conditions characterized by rapid heart rate.
• Coronary heart disease: Dicyclomine may worsen ischemia and infarction in patients with coronary heart disease.
• Hypertension: Dicyclomine should be used with caution in patients with hypertension 2.

From the Research

Dicyclomine in Heart Failure and Atrial Fibrillations

• Dicyclomine is an anticholinergic medication that can have adverse effects on the heart, particularly in patients with heart failure and atrial fibrillations.
• There is no direct evidence in the provided studies that discusses the use of dicyclomine in heart failure and atrial fibrillations.
• However, the studies suggest that atrial fibrillation and heart failure are associated with worse outcomes, and management of these conditions is crucial to prevent complications such as stroke and heart failure hospitalizations 3, 4, 5.
• The use of anticholinergic medications like dicyclomine may be contraindicated in patients with heart failure and atrial fibrillations due to the potential for adverse effects on the heart, although this is not explicitly stated in the provided studies.
• The management of atrial fibrillation in patients with heart failure and reduced ejection fraction has shifted towards non-pharmacological rhythm control, such as catheter ablation, which has shown superiority in improving survival, quality of life, and ventricular function compared to antiarrhythmic drugs and rate control therapies 3, 5.
• The use of oral anticoagulants is recommended for patients with atrial fibrillation and an estimated risk of stroke or thromboembolic events of 2% or greater per year, although the use of anticoagulation therapy in heart failure patients in sinus rhythm is not generally recommended due to the risk of major bleeding 5, 6.