Cyclosporine-A is an effective immunosuppressant, given for haemopoietic cell transplantation both in prophylaxis and in therapy of the graft-versus-host disease. Introduction of cyclosporine-A improved the results and survival of patients after transplantation. Its administration has, besides immunosuppressive effects, also adverse effects such as gingival hyperplasia, hypertrichosis, hepatotoxicity, nephrotoxicity, hypertension and neurotoxicity. This work presents 3 patients following allogenous HLA-identical transplantation of haemopoietic cells, in whom neurotoxicity of grade III developed during cyclosporine-A usage. Cyclosporine-A was in all patients given in prophylaxis and later also in therapy of the graft-versus-host disease. Neurotoxicity manifested itself as epileptic seizure with impaired consciousness, aphasia and postictal hemiparesis. After early discontinuation of cyclosporine- A, the clinical symptoms, as well as CT and MRI changes in the brain, regressed completely in all the patients.

        Key words: cyclosporine-A, neurotoxicity, haemopoietic cell transplantation, graft-versus-host disease