Hello, Welcome to HCM and thanks for your query. There is an increasing number of reports on the use of tacrolimus in nephrotic syndrome. In idiopathic nephrotic syndrome, corticosteroid treatment constitutes the first-line therapy to achieve remission. In the case of steroid resistance or steroid dependence, alternative immunosuppressive strategies are needed. Cyclophosphamide and ciclosporin are well-established drugs in this condition. There are studies which prove safety and clinical efficacy of tacrolimus in steroid-resistant and steroid-dependent nephrotic syndrome. So have no fears if your son s doctor has advised Prograf. Best wishes, Dr Noble Zachariah