amiodarone-hydrochloride and Actiq Interactions
Interactions between amiodarone-hydrochloride(amiodarone) and Actiq (fentanyl)
amiodarone and fentanyl (Major Drug-Drug)
MONITOR CLOSELY: Amiodarone may increase the risk of cardiovascular complications during or after general anesthesia with fentanyl. The mechanism of interaction is unknown. Severe refractory vasodilatation, hypotension, bradycardia, myocardial depression, low cardiac output, increased pacemaker dependency, heart block, and other conduction defects have been reported during surgical procedures involving fentanyl. Treatment has included inotropic support and pressor agents, but fatality has occurred despite these measures. Causality has not been clearly determined due to the presence of other medications in reported cases as well as conflicting data in some studies. One study consisting of patients undergoing coronary artery bypass grafting or valvular surgery found no adverse hemodynamic effects of short-term amiodarone during fentanyl-isoflurane anesthesia.
MANAGEMENT: Patients receiving fentanyl in combination with CYP450 3A4 inhibitors such as amiodarone should be carefully monitored, and dosage adjustments made accordingly if necessary. Patients and/or their caregivers should be advised to seek medical attention if potential signs and symptoms of toxicity occur such as dizziness, confusion, fainting, extreme sedation, bradycardia, slow or difficult breathing, and shortness of breath. Patients treated with transdermal formulations of fentanyl should be cautioned that drug interactions and drug effects may be observed for a prolonged period beyond removal of the patch, as significant amounts of fentanyl are absorbed from the skin for 17 hours or more after the patch is removed. Patients receiving fentanyl-containing anesthesia should be closely monitored for hemodynamic instability and other cardiovascular complications, and appropriate measures taken as required.
