Urinary TNF-alpha excretion correlates with proteinutia in patients with membranous nephropathy (MGN). Pentoxifylline suppresses or reduces the production of TNF-alpha. Between April, 1999 and August, 2000, we did a single-centre, prospective, pilot study to assess the effects of pentoxifylline (1200 mg/day) on proteinuria in patients with idiopathic MGN. Ten patients were included and treated fore months. Pentoxifylline significantly decreased proteinuria from 11 g/day [range 4.6-27] to 1.8 (0-10.9); p=0.001). Pentoxifylline may be a safe and effective adjunct to steroids and immunosuppressants in patients with MGN.