Why is amiodarone given alone?

The honest answer is that amiodarone works so great, it makes doctors that don't care about the side effects, look so good, so they prescribe it before any other drug or minerals such as potassium and magnesium. This is the black box warning put out by the company! Most doctors will never tell you about it and the side effects, or the testing that needs to be done before, starting of the drug. Black box warning! Oral route(tablet)
amiodarone oral tablet is intended for use only in patients with the indicated life-threatening arrhythmias because its use is accompanied by substantial toxicity. Amiodarone can cause pulmonary toxicity (hypersensitivity pneumonitis or interstitial/alveolar pneumonitis) that has resulted in clinically manifest disease at rates as high as 17% in some series of patients. Pulmonary toxicity has been fatal about 10% of the time. Obtain a baseline chest x-ray and pulmonary-function tests, including diffusion capacity, when therapy is initiated. Repeat history, physical exam, and chest x-ray every 3 to 6 months. Amiodarone can cause hepatoxicity, which can be fatal. Obtain baseline and periodic liver transaminases and discontinue or reduce dose if the increase exceeds three times normal, or doubles in a patient with an elevated baseline. Discontinue if the patient experiences signs or symptoms of clinical liver injury. Amiodarone can exacerbate arrhythmias. Initiate in a clinical setting where continuous electrocardiograms and cardiac resuscitation are available. Hope this helps you to make an informed decision!