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    Created in 2008, Phoenix Rising is the largest and oldest forum dedicated to furthering the understanding of, and finding treatments for, complex chronic illnesses such as chronic fatigue syndrome (ME/CFS), fibromyalgia, long COVID, postural orthostatic tachycardia syndrome (POTS), mast cell activation syndrome (MCAS), and allied diseases.

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  1. Pyrrhus

    Orthostatic Intolerance (OI) Basics: Dysautonomia of Blood Vessels, Low Blood Volume, and Baroreflexes

    I just read a good overview article covering all the basics of orthostatic intolerance: Common Syndromes of Orthostatic Intolerance (Stewart, 2013) https://www.ncbi.nlm.nih.gov/labs/pmc/articles/PMC3639459/pdf/peds.2012-2610.pdf (or https://dx.doi.org/10.1542/peds.2012-2610) This paper starts...