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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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Search results

  1. J

    Why Does B12 Cause Negative Effects?

    Hi there. I am person #1. I think it's important to know that at the beginning of my illness, my b12 serum levels were consistently elevated. At that point I didn't have a diagnosis and this was one of the few abnormalities I had in my bloodwork (the other was elevated IgA and d-dimer, a...