I think the decision over having a lip biopsy should be made according to what you personally would gain by having a diagnosis of Sjogrens. In my case I'd have a hundred more for the result it gave - i.e. very high numbers of lymphocytes on each salivary gland. But if you are already diagnosed and treated for RA and you know that you do have RA, then I'd be wary of having a biopsy. The drugs for RA can mask and give false negatives and treatments are similar anyway.

Secondary Sjogrens can be just as severe and debilitating as primary Sjogrens so knowing you have it is the thing. It helps to have your doctors looking out for Lymphoma though as having Sjogrens significantly increases your risk.

Personally I have no more numbness from my lip biopsy than I previously suffered (a fair bit) and barely a scar to show that I had it done 4 months ago. However my rheumy said he couldn't recall the last positive of this kind that he'd seen so I may be quite unusual in this respect.

For me it's very worth knowing that Sjogrens is my significant disease just for peace of mind and long journey and research and powerful instincts and some battles with the Scottish medical profession, all vindicated at last!
As I can't tolerate the RA meds or symptomatic drugs I am in two minds about treatment options although I'd love to at least be offered IViG or Rituximab and would settle for trying Cellcept/ Mycophenolate. I do think Sjogrens is a seriously underestimated disease and I get very cross that other rheumatic and neurological diseases take precedence with big gun medications.