New York, Sep 1 (IANS): A commonly prescribed antidepressant may help stroke survivors improve movement and coordination even when rehabilitation after the stroke incidents gets a little delayed, new research has found.

An estimated 65 percent of stroke survivors experience some weakness or paralysis of their limbs, and difficulty in walking and moving due to the death of brain cells from lack of blood flow.

While it is know that earlier the rehabilitation starts for stroke victims, better is the recovery, this new study has showed that the drug fluoxetine, often sold under the trade name Prozac, prolongs the time after a stroke during which physical therapy remains effective for recovering lost motor function.

"For rehabilitation to be effective, it needs to start as soon after a stroke as possible," said lead author of the study Steven Zeiler, assistant professor of neurology at the Johns Hopkins University School of Medicine in Maryland, US.

"But with this study, we have shown that in mice, we can extend the time period during which rehabilitative intervention has an effect on meaningful recovery," Zeiler noted.

When the researchers administered fluoxetine daily to the mice beginning 24 hours after inducing stroke, the mice recovered the ability to do the learned task even if they started rehab after a week's delay.

The researchers believe that the drug changed the way the brains of the mice responded to retraining.

"We believe the drug is changing the way individual neurons are responding to sensory input after the stroke," Zeiler said.

"Time still matters; it is key," Zeiler cautioned.

The mice that fully recovered motor function were started on fluoxetine immediately after the induced stroke; if fluoxetine administration was delayed by one week after stroke, instead of 24 hours, the mice did not fully recover.

The findings were detailed in the journal Stroke.