Effect of probucol on the concentration of cyclosporin A in patients with nephrotic syndrome

The first choice of therapy for nephrotic syndrome is steroid, and cyclosporin A (CyA) or other immunosuppressants are selected for steroid resistant or recurrent cases. Nephrotic syndrome accompanies hyperlipidemia for which HMG-CoA reductase inhibitors are mainly used. On the other hand, probucol is used in cases showing inadequate effects or some adverse reactions under treatment with HMG-CoA reductase inhibitors. Recently, we experienced several cases whose blood levels of CyA were decreased to about half that before the combined use of probucol, and concomitant administrations were discontinued. Based on these cases, we considered that the use of probucol should be proscribed in patients with nephrotic syndrome accompanying hyperlipidemia giving preference to CyA treatment. In cases of unavoidable usage of probucol, CyA dose adjustments are required on the basis of frequent CyA blood level monitoring.