The area under the concentration-time curve (AUC) of cyclosporin (cya) is the best indicator of its absorption and beneficial effect in RTR. 65 patients of RTR were prospectively evaluated with paek cya blood level (C2) and AUC monitoring for one yaer. Cya trouph level (C0) and C2 were correlated with the calculated AUC according to Keowon et al algorithm. Equal number of matched patients treated with C0 monitoring were selected as historical control for comparison. There was no significant difference in the incidence of acute rejection episodes (P = 0.104),cyA nephrotoxicity, proteinuria, serum creatinine, as well as graft and patient outcome between both groups. C2 guided by the abbreviated AUC in this study was less by 27 to 32% than the advised C2 in other studies. Correlation co-efficient was <70% for C0 (P<0.02) and >90% for C2 (P<0.001) in relation to AUC. The abbreviated AUC was around 6000 ng/ml/h early post transplant and gradually decreased to around 3000 ng/ml/h by the end of the study which are adequate therapeutically. We conclude that C2 has an excellent correlation with AUC compared with C0.Calculating AUC using C0 and C2 will allow less and effective cya drug exposure than using C0 or C2 alone.