[Edit - When I say "sugar" I mean either glucose, fructose or sucrose (table sugar) ] I found a web page that talks about oral rehydration therapy -- http://rehydrate.org/ors/ort-how-it-works.htm I realize that this web page is describing therapy for people (mostly infants and children) who have dehydration due to diarrhea and vomiting (e.g., cholera). But I wonder if any part of the scientific discussion of rehydration therapy also applies to folks who have either dehydration or low blood volume and have some kind of Orthostatic Intolerance? (POTS, NMH/NCS) Here's the part where it talks about the difference between plain saline vs. when glucose is added: So, is there anyone out there who understands this science and can tell whether this applies to our patient population? I'd love to know if this is why sometimes (not always!) solutions like pedialyte (or generic versions) seem to help me so much more than just water/salt/potassium, without any sugar. My other thought is maybe sometimes I just need more potassium. One liter of pedialyte has 20 Meq potassium. My daily prescription of Klor-Con has half of that, 10 Meq. Here's a much longer extract from the web page for those who want to read more: Thanks in advance to any scientist(s) out there who can understand this and can shed some light!