You may have not yet read this, but it isn't just the sun that can trigger flares - also a lot of the big box stores that are full of fluorescent lights can be a problem.
Unfortunately I can't think of anything that helps once it's been triggered - just the normal things you might do for a sunburn to sooth the skin, plus drink plenty of water & get as much rest as possible.
Plaquenil doesn't really treat the disease, it inhibits disease progression. Plus it takes a couple of months to really start working. I don't know when your next appointment is, but if you are having problems with symptoms you may want to get an earlier visit. Often prednisone is added initially to get inflammation under control.
Lynnwood, Lupus & Sjogren's Moderator, Dx: 2000DIAGNOSING LUPUS & HW's LUPUS 101
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