In 2010, I began experiencing episodes where my blood pressure would spike really, really HIGH, then drop down to normal after several minutes, and continue to do this OVER and OVER again for an hour or so. Then my BP would go back down to normal and stay there. My blood pressure stayed within normal range the rest of the day but would spike like that again the very next day. I made an appointment with a cardiologist, who ran numerous tests on my heart, etc., which all came back normal. He determined that I was not hypertensive/did not have hypertension. He asked me if anything had changed, if I had started taking a new medication, etc. I told him that the only thing that had changed with my medications was that my Primary Care doctor had adjusted my thyroid medication (Synthroid for Hypothyroidism) and had raised the dosage from 125 to 150. And that I had started taking it the very same day that I began experiencing the BP spikes. That's when I realized that the episodes would start about 2 hours after I took the Synthroid. My cardiologist said that it was possible that it could be what was affecting my blood pressure. The next day, I went back to taking the lower dose of Synthroid and the BP spike episodes STOPPED. I did not have another episode after that. After that, I asked my PC about increasing the dose of Synthroid in smaller increments, just in case. I'm not suggesting that this could be the issue in your case. I just wanted to mention this to show that there could be something else going on in regard to other organs in your body, specifically the glands. The thyroid, adrenal, parathyroid, and other glands produce hormones that regulate various bodily functions. You might want to ask your cardiologists about that.