At present, alteplase [rt-PA] is the only thrombolytic drug approved for use in acute ischaemic stroke and it must be administered within 3 hours of stroke onset. Data reported at the 24th International Conference on Stroke and Cerebral Circulation [Nashville, US; February 1999] included contradictory reports on the effectiveness of alteplase administered up to 6 hours after stroke onset, the use of alteplase in clinical practice and the promising efficacy of other thrombolytic drugs.