I have low blood pressure within the last month or two. I have had runny greenish brown diarrhea within the past two to three weeks, daily, several times a day. I take two high BP meds, my dr. took me off one high BP med two weeks ago. I was taking three high BP meds the last five yrs. or so. This has recently started and I have fallen twice without any symptoms to warn me before hand. Just fell to floor, at home. Get dizzy if I stand up to fast and have had the low BP the last month or two, including diarrhea within the past two to three weeks. What may be the cause of this?