Virginia- 71 yrs. 5'2" 205# On lisinopril / hydrochlorothiazide for over 15 yrs. BP average 138/60. My husband and I started a low sugar diet in January, because both of us were noticing higher A1C glucose levels. (not diabetic) In May, I had been feeling tired and light-headed, My husband took my BP and found it at 105/55. Over several days, it remained at that level. I quit the lisinopril / hydro and my BP over the last 6 weeks has been 135/58 on average. My weight has remained constant. (We dairy farm and I still am quite active). My problem is I have been getting cluster head-aches in the forehead and temple area for about the time I've been off the lisinopril / hydro. Is this withdrawl?