A drug now approved by the Food and Drug Administration to treat high blood pressure has been found to be effective in treating alcoholism and drug addiction.

Researchers at the University of Texas at Austin were able to halt cocaine and alcohol abuse in experiments involving laboratory rats. If the treatment proves effective in humans, it would be the first to help prevent relapses by erasing the unconscious memories that underlie addiction, Medical Xpress reports.

The research, published in the journal Molecular Psychiatry, builds on past studies that have shown environmental cues — the people, places, sights, and sounds an addict experiences leading up to drug use — are key triggers of relapses.

Lead researcher Hitoshi Morikawa, associate professor of neuroscience, and colleagues trained rats to associate either a black or white room with the use of a drug, so that addicted rats nearly always chose the room associated with their addiction.

But after the researchers gave the addicted rats a high dose of an antihypertensive medication called isradipine they no longer showed a preference for the room associated with their drug.

"The isradipine erased memories that led them to associate a certain room with cocaine or alcohol," said Morikawa.

"Addicts show up to the rehab center already addicted. Many addicts want to quit, but their brains are already conditioned. This drug might help the addicted brain become de-addicted."