RT Journal Article SR Electronic T1 Pancytopenia related to azathioprine in rheumatoid arthritis. JF Annals of the Rheumatic Diseases JO Ann Rheum Dis FD BMJ Publishing Group Ltd and European League Against Rheumatism SP 503 OP 505 DO 10.1136/ard.47.6.503 VO 47 IS 6 A1 M E Jeurissen A1 A M Boerbooms A1 L B van de Putte YR 1988 UL http://ard.bmj.com/content/47/6/503.abstract AB Two patients with rheumatoid arthritis developed pancytopenia during treatment with azathioprine 100 mg daily. In one patient this side effect occurred after three weeks, in the other after eight weeks of treatment. Rapid fall of platelets in one patient necessitated platelet transfusion. In the other patient additional treatment with allopurinol was probably responsible for the toxic effect. Haematological side effects of azathioprine are discussed.