Should imdur oral b used prn or should it b taken all the time?not exp. chest discomfort rt now.

Never PRN: Imdur is a slow release medication meant to prevent angina. It is of little benefit once there is an attack because it will not work for hours. If there is no angina, perhaps the dose could be reduced or the medication may no longer be needed. Dosing should be once daily in the morning and not more or less frequently. Talk to your doctor about whether to wean off this medication.