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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. R

    High Cholinesterase enzyme activity

    Has anyone seen high levels of High Cholinesterase enzyme activity in serum? My levels are 439 U/L while the reference range is 170- 420 U/L I have gut issues, food sensitivities and anxiety issues. Was wondering if I have high levels of Acetylcholine. Any thoughts