What Causes Dizziness While On Blood Pressure Medication?

feeling faint in face when starting to fall asleep or even while alert and active. Almost seizure like, no twitching, etc., just like onset of seizure or fainting. Always feel it in my face, mostly when tying to fall asleep. Had 1 grand maul seizure in 2007 and take carbazamine to prevent more. Am on anxiety meds and blood pressure meds. This is not a new occurrence for me, has been going on for probably 20 years...swallowing or moving will stop the sensation. Have had family and friends observe this and describe it as a blank stare and slow to respond.