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.
Also, bradycardia sometimes is a side effect of certain medications, including propranolol (Inderal), atenolol (Tenormin), metoprolol (Toprol-XL), sotalol (Betapace), verapamil (Calan, Isoptin, Verelan) and diltiazem (Cardizem, Dilacor-XR).