People who have had strokes due to bleeding on the brain may be able to take aspirin safely, a study suggests.
There have been concerns over potential side effects of aspirin
Anyone whose strokes are caused by clots are already given aspirin to prevent more forming.
But the drug can cause bleeding, so is rarely given to people who have had haemorrhages - even though they are also at risk of clot-based strokes.
However, stroke experts urged caution over the Massachusetts General Hospital findings, published in Neurology.
Haemorrhagic and ischaemic strokes, the kind caused by clots, have many of the same risk factors - such as poor diet and smoking - so doctors look for preventative treatments which can reduce the risk of both.
Every year, over 150,000 people in the UK have a stroke, most of whom are over 65.
Stroke is the third most common cause of death in the UK. It is also the single most common cause of severe disability.
The researchers followed a group of 207 patients who had survived a intracerebral haemorrhage during the period from 1994 to 2004.
In an intracerebral haemorrhage, a blood vessel bursts within the brain resulting in a pressure build-up that can lead to unconsciousness or death.
They were surveyed by telephone every six months and asked about any recurrence of haemorrhage or other neurological disorders and whether they took aspirin or other antiplatelet (clot preventing) therapies.
No greater risk of a recurrent haemorrhage was seen in the 46 who took aspirin, compared to the 161 who did not, during the 20 month follow-up period.
Dr Eric Smith, who led the research, said: "While it would be premature to conclude that all patients with intracerebral haemorrhage can safely take aspirin, our results suggest it may be appropriate for some patients at elevated risk of ischemic stroke or heart disease."
He added: "The most definitive information would come from a clinical trial in which patients were randomly assigned to receive aspirin or a placebo [dummy version].
"But I think such a trial is unlikely, so this may be the best data that will be available."
However, in an editorial in the journal, Larry Goldstein, a neurologist at Duke University in North Carolina, said it was uncertain whether the patients in the study had actually benefited from these drugs.
He added: "Until additional data become available, the use of antiplatelet drugs in this setting should be restricted to highly selected patients with a compelling indication and a relatively low risk of recurrent haemorrhage."
Dr Tony Rudd, president of the British Association of Stroke Physicians, said: "The problem this study addresses is a common one as people who suffer haemorrhage into the brain are often those who also have heart disease, and indeed, the other type of stroke."
He added: "This study is reassuring that it is possible to give aspirin to some patients without massively increasing the risk of recurrent brain haemorrhage.
"However it looked at only a small group of patients and therefore a modest increase in risk may not have been identified.
"I think we should continue to use drugs such as aspirin with caution in people who have haemorrhagic stroke."