I have been taking lisinopril for four days and that four days too many. I started taking these pill on Monday. Tuesday i went to the ER because i thought i was having a stroke. I was having chest pains and my left arm went numb. I had just had an EEG, EKG, a Cat Scan and a stress test. Each one showed my heart was fine. ER doc's could not fine anything wrong, so i went home and took my next dose as scheduled. I kept experiencing these chest pain/arm numbness off and on all day Wed. That night i could not sleep because the symptoms are worse when you lay down. I went to doctor on Thursday and described my symptoms. She thought it was strange that I was having continuous pain, so she scheduled me an appointment with a cardiologist. Today (Friday) i kept trying to figure out what had changed that would cause these pains/numbness. I started reading the literature that comes from pharmacist. Low & behold chest pains was listed as a side effect. I have decided to stop taking this medicine with the hope these pains/numbness will go away.