According to the National Institutes of Health, "there is not enough scientific evidence to firmly establish that any [complementary and alternative medicine] therapies are safe and effective for RA." It warns against replacing proven medical treatment with unproven alternatives.
However, the NIH's National Center for Complementary and Alternative Medicine says some mind-body therapies (such as meditation or tai chi) or supplements (such as fish oil) may be helpful additions to conventional treatment. It cautions, though, that some supplements may interact with medication.
Consult your doctor before starting any alternative treatment.