I woke up in the middle of the night to get a drink of water. I was overcome by a sudden wave of nausea and my vision began to gray out. As I felt my way back to the bedroom, it became difficult to walk....feet felt like lead. After a few minutes it all passed, but I was left feeling rather weak. I m a 42 year old female with high blood pressure. I currently take lisinopril . I have medullary kidney disease and nephrocalsinosis. Kidneys function is okay, but I take hydrochlorothiazide as a precaution against kidney stones . Heart disease is an issue in my family, as well as stroke.