I was in the hospital in December and they did a set of orthos on me and said I have orthostatic hypotension too. It was a malnutrition/dehydration thing for me. I had another set of orthos done earlier this year and my bp still dropped more than most people's but not enough to be considered significant and meet dx criteria.
I was told to just get up slowly and hold on to something when going from laying down/sitting to standing.