Methods, formulations, dosing regimes, and routes of administration for the treatment or prevention of arrhythmias, including the treatment or prevention of atrial fibrillation. In these methods, the disease or condition is treated or prevented by administering one or more ion channel modulating compounds to a subject, where the ion channel modulating compound or compounds produce specific plasma levels in the subject. The ion channel modulating compounds may be cycloalkylamine ether compounds, particularly cyclohexylamine ether compounds.