question: I am a 63 yr old female, taking 80mg of Pravastin a day.  I have had consistent hypertension for 10 years or so, and a fill in M.D. for my internist just prescribed 5 mg of Lisinopril, which has been doing miracles for a month.  "Old" internist wants a fasting blood test before she will extend the Lisinopril prescription.  Why?