All stroke patients should be given a brain scan within 12 hours after the onset of symptoms, doctors have said.
Waiting 24 hours for the scan is no longer acceptable, leading physicians said as they called for the timeline to be reduced by half.
All patients, no matter how old, should be considered for clot-busting treatment if they have suffered an ischaemic stroke, caused by a blockage in the arteries that supply blood to the brain, according to the Royal College of Physicians (RCP) which has issued new guidance on stroke treatment.
In the past thrombolysis was only recommended for people under the age of 80 but the RCP has called for patients of all ages to be offered the treatment within three hours of a stroke.
It also called for a streamlining of stroke services across England and Wales so patients have "seamless" care.
Professor Tony Rudd, chair of the intercollegiate stroke working party at the RCP, said: "Stroke is a complex disease that requires the skills of multiple professionals to ensure the best-quality outcome and the best use of resources.
"This guideline summarises a wealth of evidence and provides expert consensus statements on areas where the evidence is lacking.
"No professional should ever use the excuse that they don't know what the evidence is for treating stroke patients. The patient version of the guideline ensures that patients know what care they should be receiving."
Ischaemic stroke accounts for 80% of strokes.
In England and Wales around 130,000 people have a stroke each year and accounts for an estimated 43,000 deaths.