Daily bisphosphonate is effective in preventing and treating corticosteroid-induced osteoporosis in renal transplant recipients, although it frequently has gastrointestinal side effects. The aim was to assess efficacy and side effect profile of weekly oral risedronate. Eighty-four renal transplant patients, receiving either cyclosporin A or tacrolimus and steroids were prospectively included. The study group (39 patients) received 35 mg risedronate weekly, vitamin D and calcium, while control group (45 patients) only vitamin D and calcium. At baseline, 6 and 12 months, creatinine, calcium, phosphorus, alkaline phosphatase and iPTH were determined. Fractures and bone mineral densities were assessed by X-rays and dual-energy X-ray absorptiometry, respectively. Pain was assessed by clinical interview. Mineral bone density score increased significantly in risedronate group after 1 year. There were no differences in the incidence of fractures, although, anamnestic pain assessment revealed that 3% of treatment group reported to have bone pain compared with 18% in nontreatment group (P < 0.05). Follow-up calcium, phosphorus, alkaline phosphatases, and iPTH levels showed no differences from basal measures. Risedronate was well tolerated with no major side effects. Weekly oral risedronate in renal transplanted patients reduces bone mineral loss and bone pain and has an excellent side effect profile.