We report a case of leucoencephalopathy with tremor and generalized motor seizures a few days after introduction of cyclosporin A (Cy A) in a kidney recipient. There was a relationship between acute neurological symptoms and high and sudden blood level of Cy A (1 260 ng/ml; therapeutic range: 120-275 ng/ml). White-matter hypodensities at CT scanning and severe slow-waves abnormalities at EEG were present. All neurological symptoms were reversible after Cy A level was lowered. Three months later, a blood Cy A level at 217 ng/ml due to nicardipine co-administration resulted in severe tremor and was reversed by decreasing blood Cy A level to 126 ng/ml.