Sometimes with Lupus you can feel the prednisone calm the flare quickly, but usually it works more slowly. Probably because a Lupus flare is much more systemic than a sinus infection.
If you feel like the prednisone helped more than just the sinus infection, you might want to visit a rheumy who is experienced in making Lupus diagnoses and treating Lupus. One reason to do this is because some Drs use prednisone to help differentiate between a Lupus dx and a Fibro dx -- Lupus generally responds to prednisone, Fibro usually does NOT respond to prednisone.
If you do have Lupus, you'll want to, at minimum, be on Plaquenil to help slow the disease.
Lynnwood, Lupus & Sjogren's Moderator, Dx: 2002DIAGNOSING LUPUS & HW's LUPUS 101
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