This might be a bit long so bear with me - I'm 33 y/o male, family history of high BP, I was borderline for most of my 20's and when I turned 30 my doctor finally put me on Benicar. For three years my BP has been perfect, although recently I began an extremely vigourous exercise/training program (I've been an athlete all my life so I didn't go from no activity to lots of activity) so a few times it dipped kinda low 90/60, and while I never really felt any dizziness my doctor did tell me that was low. Then my insurance company initiated a step program basically forcing me to change meds, so given that my BP was very low anyway he gave me a prescription for Hydrochlorothiazide, so I stopped taking the Benicar for a week and then started taking the HCT one week ago. In the last week I've had uncomfortable/uncontrollable palpitations (I've had them for close to ten years but not as frequent, I'm talking all day and night long), and had dizzy spells pretty frequently, and a feeling of weakness sort of like when you have real low blood sugar/energy. So, this week I skipped my hardcore training (mixed martial arts), and stuck with some relatively low intensity cardio workouts on an elliptical at the gym. Yesterday during this low intensity workout I had an extremely sharp sensation of pain shoot through my left temple, and my vision got immediately blurred, I also got extremely dizzy and almost fell off the elliptical, I pretty much almost passed out. So, I've decided to stop taking the HCT until I can figure out what is wrong, there is no way I can deal with these kinds of side effects for the rest of my life. Is this common with HCT? Or is it just my body freaking out b/c of some withdrawal from the Benicar? Oh, and the Benicar I was taking was just straight Benicar (the lowest dose I think it was 25 mg) without the HCT. Any advice would be appreciated, as I lead a very active lifestyle and right now I feel terrible b/c I'm afraid to do anything.