DALLAS (AHA) -- For the first time, research has shown that high doses of acetaminophen can lower body temperature and may limit the debilitating effects of stroke, even in patients who don't have a fever, researchers report in the July issue of Stroke: Journal of the American Heart Association.

Fever in the first 12 to 24 hours after a stroke is a strong predictor of how severe the effects of the stroke will be. However, it is unknown if fever-reducing drugs, such as acetaminophen, can be helpful, even if patients do not have a fever. Some research has examined ways to induce hypothermia (lowered body temperature) in some feverish stroke patients.

In the first randomized, double-blind clinical trial, Dutch researchers investigated if early use of the drug acetaminophen in those who had an ischemic stroke but did not always have fever, would reduce body temperature. An ischemic stroke is caused by a blood clot that reduces blood flow to the brain.

The study compared 75 patients with ischemic stroke whose temperatures were between 36 degrees Celsius (96.8 degrees Fahrenheit) and 39 degrees Celsius (102.2 F). They were treated with acetaminophen or placebo six times a day for five days.

Individuals treated with the higher dose of acetaminophen had temperatures 0.4 degrees Celsius (.72 F) lower than placebo treatment after 24 hours of treatment. By day five, there were no differences in temperatures between any of the groups.

The researchers note that the small initial drop in temperature is significant considering that a previous observational study suggested a two-fold increase in the risk of death for every one degree Celsius rise in body temperature.

Acetaminophen's effect on temperature may be worthwhile, given the low cost and safety of the drug, the researchers note. Their next, larger study will be directed at demonstrating the effect of acetaminophen on stroke outcomes. These results may also prompt more research into medical means to decrease stroke and improve outcomes.