In an open pilot study 55 patients suffering from acute stroke were treated with Flunarizine, a calcium overload blocker, in addition to standard therapy including diet, physiotherapy, adequate management of accompanying disorders, and hemodilution. The initial high-dose i.v. treatment (2 X 25 mg Flunarizine/day) and the subsequent oral regimen were well-tolerated. The main side effect was slight transient weariness. No adverse effects regarding blood pressure, heart rate, enzymes, blood analysis, renal function and, especially, no extrapyramidal motor symptoms or depression were detected. Flunarizine may be regarded as a relatively safe drug in acute stroke. The probable beneficial effect on the patient's recovery will be evaluated in a multicenter double-blind study.