Intravenous thrombolysis
Intravenous alteplase (recombinant tissue plasminogen activator) is effective when given within 4.5 hours of onset of symptoms of acute ischaemic stroke. Earlier treatment has better outcomes, so when alteplase is indicated1, it should start as soon as possible after stroke onset. The main adverse effect of alteplase is bleeding, including symptomatic intracranial haemorrhage.
If the patient has raised blood pressure, this should be treated before starting thrombolysis. Local hospital protocols should be followed to reduce the blood pressure to 185/110 mmHg or lower—possible drugs include glyceryl trinitrate and labetalol. Thrombolysis should not be started if the blood pressure can't be lowered to this level.
Intravenous alteplase should be given in a setting with expert staff. Blood pressure and neurological status should be monitored for 24 hours after alteplase infusion. If blood pressure exceeds 185/110 mmHg, it should be treated promptly, aiming to maintain it below this level. Aspirin should be withheld for 24 hours, to minimise the risk of haemorrhage.