Scientists have discovered a drug approved by the U.S. Food and Drug Administration (FDA) to treat high blood pressure could also effectively treat alcohol and cocaine addictions.

The medication could be the first ever to prevent relapses by erasing the unconscious memories related to the addiction, the University of Texas at Austin reported.

To test the potential treatment, a team of researchers trained rats to associate either a black or white room with the use of a drug. When the rats were given a choice between the two rooms, they almost always entered the one associated with the drug they were addicted to. The rats were then given a high dose of the hypertension drug isradipin. The rats still showed a preference for the drug-associated room that day, but in subsequent days proved to lose their preference.

"The isradipine erased memories that led them to associate a certain room with cocaine or alcohol," said Hitoshi Morikawa, associate professor of neuroscience at The University of Texas at Austin.

Addictive substances are believed to rewire brain circuits involved in reward learning, causing strong drug-related memories. Antihypertensive drugs block an ion channel present in certain brain cells, reversing the rewiring that creates the memories of addiction-associated places.

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

The findings were published in a recent edition of the journal Molecular Psychiatry.