<s>[INST] I m taking Celebrex for after orthoscopic knee surgery. Generally once a year, my other knee will just swell up for no reason. It is currently doing that, but my question is, how can my knee swell up when I m on a NSAID already? And is there anything I can take in addition to the Celebrex to get the swelling down? Thank you. Vicki [/INST] This case mostly of autoimmunodeficiency ,so you need to do some lab invetigations such Rheumatoid factor, blood sugar, CBC and detect other autoimmune factors also. </s>