Doctor put me on this med called Isosorb mono er 60 mg and i took my first pill tonight and it has gave me a massive headache . I took it around noon today and just had a mild one at first but i took a nap and boy did i wake up to a massive one . Also my back on both sides at the bottom hurts . Can anyone tell me how long this pill will take to get out of my system . Remind you i have only took 1 and tomorrow i will be calling the doctor to get it changed or stopped cause i cant deal with this type of side effect . It hurts typing this .