Brugada pattern can be found on the electrocardiogram (ECG) of patients with altered mental status, usually with fever or drug intoxication. Diagnosis remains challenging, because the ECG changes are dynamic and variable. In addition, triggers are not always clearly identified. In patients with atrial fibrillation (AF), the use of class IC antidysrhythmic drugs can unmask a Brugada pattern on the ECG, especially if combined with other medications acting on sodium channels.