Does amiodarone cause constipation?

Amiodarone and Constipation

Yes, amiodarone does cause constipation as one of its gastrointestinal side effects. Constipation, along with nausea and anorexia, are common gastrointestinal adverse effects associated with amiodarone therapy 1.

Gastrointestinal Side Effects of Amiodarone

• Constipation is a well-documented gastrointestinal side effect of amiodarone therapy 1
• These gastrointestinal symptoms are often dosage-related, meaning higher doses are more likely to cause constipation 1
• In addition to constipation, other common gastrointestinal effects include nausea and anorexia 1
• Gastrointestinal side effects were reported in 56 out of 70 patients (80%) in one early study, with constipation being the most common manifestation 2

Management of Amiodarone-Induced Constipation

• Reducing the dosage of amiodarone often leads to improvement in constipation and other gastrointestinal symptoms 1
• The lowest effective dose of amiodarone should be used to minimize adverse effects 1
• Physicians must monitor for this and other side effects, as virtually all patients develop some side effects when maintained on higher doses (e.g., 600 mg daily) 2

Other Important Adverse Effects of Amiodarone

While constipation is common, it's important to be aware of other potentially more serious adverse effects:

• Pulmonary toxicity: The most serious potential adverse effect, presenting as subacute cough and progressive dyspnea 1
• Thyroid dysfunction: Both hyperthyroidism and hypothyroidism can occur 1
• Liver toxicity: Manifested by elevation of liver transaminase levels 1
• Ocular effects: Corneal microdeposits visible on slit-lamp examination in nearly all patients 1
• Dermatologic effects: Photosensitivity is common 1
• Neurologic toxicity: Can include ataxia, paresthesias, and tremor 1
• Cardiovascular effects: Bradycardia and heart block occur in 1-3% of patients 1

Clinical Implications

• In elderly patients, amiodarone is listed as a potentially inappropriate medication due to its numerous side effects, including constipation 1
• Regular monitoring is essential for patients on amiodarone therapy to detect and manage adverse effects early 1
• For patients with significant constipation, dose reduction should be considered if clinically appropriate 1
• The anticholinergic effects of amiodarone (including constipation) can be particularly problematic in elderly patients 1

Monitoring Recommendations

• Baseline assessment should include a complete history and physical examination 1
• Regular follow-up should include assessment for gastrointestinal symptoms including constipation 1
• If constipation becomes severe or significantly impacts quality of life, dose reduction should be considered 1, 2