Abstract Background Fever, alcohol, and sodium channel blockers can unmask Brugada pattern and may also induce arrhythmias in Brugada syndrome. We report a case of unmasked Type-1 Brugada pattern presenting with ventricular fibrillation that was induced by a tetrahydrocannabinol vaping. Case summary A 48-year-old male with a past medical history of hypertension treated with hydrochlorothiazide and back pain controlled with tetrahydrocannabinol vaping presented with sudden cardiac arrest from ventricular fibrillation, which was terminated with defibrillation. Electrocardiogram after resuscitation showed a new Type-1 Brugada pattern compared to a previous normal baseline electrocardiogram. Echocardiography and coronary angiogram were unremarkable. Complete blood count and chemistries were unremarkable...