In a total of 1836 patients in controlled and uncontrolled clinical trials, 14% of patients received intravenous amiodarone for at least 1 week, 5% received it for at least 2 weeks, 2% received it for at least 3 weeks, and 1% received it for more than 3 weeks, without an increased incidence of severe adverse reactions. The mean duration of therapy in these studies was 5.6 days; median exposure was 3.7 days.
The most important treatment-emergent adverse effects were hypotension, asystole/cardiac arrest/electromechanical dissociation (EMD), cardiogenic shock, congestive heart failure, bradycardia, liver function test abnormalities, VT, and AV block. Overall, treatment was discontinued for about 9% of the patients because of adverse effects. The most common adverse effects leading to discontinuation of intravenous amiodarone therapy were hypotension (1.6%), asystole/cardiac arrest/EMD (1.2%), VT (1.1%), and cardiogenic shock (1%).
The following table lists the most common (incidence > 2%) treatment-emergent adverse events during intravenous amiodarone therapy considered at least possibly drug-related. These data were collected from the Wyeth-Ayerst clinical trials involving 1836 patients with life-threatening VT/VF. Data from all assigned treatment groups are pooled because none of the adverse events appeared to be dose-related.
SUMMARY TABULATION OF TREATMENT-EMERGENT DRUG-RELATED STUDY EVENTS IN PATIENTS RECEIVING INTRAVENOUS AMIODARONE IN CONTROLLED AND OPEN-LABEL STUDIES ( ≥ 2% INCIDENCE)
|Body as a Whole|
|Fever||24 (2.9%)||13 (1.2%)||37 (2.0%)|
|Bradycardia||49 (6.0%)||41 (4.0%)||90 (4.9%)|
|Congestive heart failure||18 (2.2%)||21 (2.0%)||39 (2.1%)|
|Heart arrest||29 (3.5%)||26 (2.5%)||55 (2.9%)|
|Hypotension||165 (20.2%)||123 (12.0%)||288 (15.6%)|
|Ventricular tachycardia||15 (1.8%)||30 (2.9%)||45 (2.4%)|
|Liver function tests abnormal||35 (4.2%)||29 (2.8%)||64 (3.4%)|
|Nausea||29 (3.5%)||43 (4.2%)||72 (3.9%)|
Other treatment-emergent possibly drug-related adverse events reported in less than 2% of patients receiving intravenous amiodarone in controlled and uncontrolled studies included the following: abnormal kidney function, atrial fibrillation, diarrhea, increased ALT, increased AST, lung edema, nodal arrhythmia, prolonged QT interval, respiratory disorder, shock, sinus bradycardia, Stevens-Johnson syndrome, thrombocytopenia, VF, and vomiting.
In postmarketing surveillance, hypotension (sometimes fatal), sinus arrest, pseudotumor cerebri, syndrome of inappropriate antidiuretic hormone secretion (SIADH), toxic epidermal necrolysis (sometimes fatal), exfoliative dermatitis, pancytopenia, neutropenia, erythema multiforme, angioedema, bronchospasm, possibly fatal respiratory disorders (including distress, failure, arrest, and ARDS), fever, dyspnea, cough, hemoptysis, wheezing, hypoxia, pulmonary infiltrates and anaphylactic/anaphylactoid reaction (including shock), hallucination, confusional state, disorientation, and delirium also have been reported with amiodarone therapy.
Also, in patients receiving recommended dosages, there have been postmarketing reports of the following injection site reactions: pain, erythema, edema, pigment changes, venous thrombosis, phlebitis, thrombophlebitis, cellulitis, necrosis, and skin sloughing (see DOSAGE AND ADMINISTRATION).