Lupus is generally diagnosed by having 4 of 11 symptoms, which I don't believe you have.
The best preventative for all kinds of disease is pretty much the same -- deep restorative sleep, regular exercise, and healthy eating.
One thing you might try for the oral bumps is a regular salt-water gargle -- it generally helps with everything oral and may even help the bump in your throat.
Lynnwood, Lupus & Sjogren's Moderator, Dx: 2002DIAGNOSING LUPUS & HW's LUPUS 101
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