Are you taking any of the meds Imuran, Cellcept, and/or MTX? Once I was able to come off of those, I realized they were the actual source of my thinning hair, not Lupus itself. Hair has come back to at least 95% of what it was originally after thinning to maybe 75% original.
Another thought is menopause or hormone imbalance - get some thyroid tests done if you haven't, that can be the source of thin hair - same with menopause. Both of these can be thrown off by prednisone -- we need to take some supplemental vitamins when taking it.
Vitamin B helps, I think. Don't remember this early. Joy is probably right in suggesting biotin (B7) and folic acid (B9) - with Lupus we are very often low in B.
Hope this helps a little!
Lynnwood, Lupus & Sjogren's Moderator, Dx: 2002DIAGNOSING LUPUS & HW's LUPUS 101
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