Hi dm, Are you on medication for this? Does it seem to help? I'd talk to the doctor about it. You might need a new medication or a second one. In the meantime, I've heard that relaxation techniques can help bring blood pressure down a little bit usually. I can bring mine down with biofeedback which is a type of meditation. However any kind should do the trick with practice. It is certaintly NOT a cure all but it might help to bring it down just a bit to stop your symptoms. ??? It is worth a shot but you'd have to practice it consistently to make a difference and it might take some time to get it mastered to the place it would do the trick. 
Good Luck and please talk to your doctor about it, too!