Within 2 days of beginning Lisinopril for an "elevated blood pressure event", I bagan to experience labored breathing, like I had just walked up 10 flights of stairs. And that was at rest! I had some anxiety and was generally lethargic. I also began experiencing severe cramps in my legs, feet, and toes. My arches would cramp so bad I coulld hardly stand it. I thought this might be related to the diuretic in the medication. I also experienced muscle weakness. I called my doctor who told me to take half a pill each day. The effects were basically the same at half the dosage! The breathing still labored, less cramping, but same feeling of tiredness and lethargy. I quit taking it, made some lifestyle changes (less sodium laced foods, more exercise) to bring down the pressure.