arrhythmia
"I'm on this medicine for heart arrhythmia. I'm 46, my heart does flip flops and super rapid beats per min. Blood pressure sometimes is 180/110. Then it drops to 96/67, that little roller coaster ride makes you ill. I started the  Calan SR 180mg tab. It gives me wicked headache in left lobe & fatigue. It hasn't helped my heart from flip flopping or blood pressure from sky rocketing up then down like a yo-yo. However, it does calm my heart down once I have a spell and I take the meds. I generally fall asleep from fatigue. It could be that I haven't taken it long enough for it to start helping the high blood pressure or the irregular heart beat. Perhaps the second month will show improvement. "