I tend toward low blood pressure as well and have collapsed onto the ground (at Safeway) when I knew I was at danger of fainting. I’m sure it looked very odd but I was not accompanied by anyone. I made sure I was OK again before driving 5 minutes home. If H had been around, I suspect he would have freaked out. I was very quiet and no one was watching at the time so no one saw me. I did speak with my MDs and they said it was likely a combo of low blood pressure and dehydration. Have never had problems since but work to be sure to stay hydrated. Am also being monitored for my low blood pressure and taking a medication that seems to help it, Midodrine. The person I am seeing is a APRN who specializes in Postural Orthostatic Tachycardia Syndrome (POTS). My D also has this issue.
I’m so sorry your husband had this issue and I’d try to schedule a visit with his primary care ASAP, explaining what happened.
My D has fainted as well for low blood pressure, as she also has POTS and is under the care of a POTS cardiologist at UCLA. There are NO POTS cardiologists in our entire state of HI. The one we had moved to TX as HI was just too dang expensive!