The immunomodulatory effect of Plaquenil (Hydroxychloroquine) is interesting. Via its modulation of toll-like receptors it may have some impact on reducing production of Interferon-alpha amongst other factors. Seeing as recombinant IFN-a inections (used in Hepatitis C) causes many but not all of the symptoms of ME - albeit I don't know the severity of the muscle weakness or 'fatigue' that is felt during high dose therapy.. Have any of you had experience of taking this drug consistently over some duration (i.e. several months or more) perhaps for those of you who have been treated for Lyme? If so what was your dose? I'm currently exploring new treatment options, this being one and Valcyte (as I had a Herx response to Famvir - but I was on quite a low dose 500mg/day and only on for about two months, which is far too short a time). My Immunoglobulin can't remeber which one is what, was high to EBV showing 'past' infection. Thanks, Energyoverload.