I've had those issues my entire life, but when I'm flaring...for sure my back and legs get much more painful (nagging/constant).
If you see a chiropractor, that can help if you do have sciatica or any back/leg pain.
You're flaring, so you really need to deal with that asap. 1000mg mesalamine oral isn't enough to deal with any flare.
I'd suggest you call your GI doctor, get on a higher dosage of oral and add rectal retention mesalamine enemas asap.
You might ask the doctor to switch you from oral mezavant to sulfasalazine which can also help with joint pain apparently. That in conjunction with rectal will help your flare.
Hope you feel better soon.
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