What Dosage Of Metpure Is Effective In Treating Irregular Heart Beat?

What dose of metpure is effective for refusing the pulse rate my wife is a patient of atrial fibrillation she has been prescribed metpurexl 12.5alongwith pradaxa110 twice a day we are now in us these medicines are bein given as usual since last two days her heart beat is fast abo v e100& irregular can I ra isle the dose of metpure & how much