Filgrastim, sold under the brand name Neupogen among others, is a medication used to treat low blood neutrophils due to a number of causes. This includes when it occurs following chemotherapy, radiation poisoning, HIV/AIDS, or is of unknown cause.
Bradycardia and heart block occur in 1 to 3 percent of patients receiving amiodarone. 2 Amiodarone-induced proarrhythmia occurs at an annual rate of less than 1 percent.
Amiodarone may cause a condition that affects the heart rhythm (QT prolongation). QT prolongation can rarely cause serious (rarely fatal) fast/irregular heartbeat and other symptoms (such as severe dizziness, fainting) that need medical attention right away.