1. Product Information Immunosporin (Cyclosporine), Novartis Pharma, last update 9/2011
2. Product Information Azulfidine RA (Sulfasalazine), Pfizer, last update 5/2009
3. Product Information Lantarel (MTX), Pfizer, last update 11/2010
4. Product Information Arava (Leflunomide), Sanofi Aventis, last update 11/2011
5. Ellman MH, Ginsberg D (1990) Low-dose methotrexate and severe neutropenia in patients undergoing renal dialysis. Arthritis Rheum 33:1060–1061