I am 39 and have been diagnosed with sinus tachycardia. They prescribed Bisoprolol 2mg to be taken once daily. But I never took any as I fear for the side effects any medication may have.Have been having tachycardia since last 6years. Just yesterday I felt my heart skip a beat and I was dizzy, breathless for a second. Then I was back to normal. But have been quite scared since then. Yes, I am not so physically active nowadays as its cold and windy out there.Need to get active.