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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. K

    Vitamin D sensitivity

    Hi, Are any of you sensitive to vitamin D supplementation? Taking more than 500 units makes me weak, dizzy, nauseous and feeling drunk. Even at this dosage, I feel tired. Is anyone familiar with this? Thanks.