Methotrexate is certainly used in treating psoriatic arthritis. As is the case in rheumatoid arthritis doses ranging up to 20-25 mg/week may be required and it may take a couple of months until the benefits of and increased dose are felt. If there is ongoing inflammation in the joints in spite of MTX, the group of medications called TNF antagonists are often used (Enbrel, Humira, Remicade). For reasons that are not well understood, some patients will feel more benefit from a change from one NSAID to another as your rheumatologist has recommended (diclofenac to celebrex).
About Clifton Bingham, III, MD
Associate Professor of Medicine
Director - Johns Hopkins Arthritis Center