Cocaine cravings can be triggered by memories. Movieclips Trailers / YouTube A new therapy could treat drug addicts by erasing their memories.

The experimental treatment, developed by researchers at Cardiff University and published in the journal eLife, can wipe clean the memories associated with taking cocaine, which is one of the main reasons users find the drug so addicting.

Cocaine produces a buildup of the neurochemical dopamine in the brain, which causes the user to feel euphoric and compulsive. This is because of its impact on the limbic system, which is an area of interconnected regions in the brain responsible for pleasure and motivation.

New memories made when high on cocaine are therefore intense and filled with enjoyment, leading the user to seek out these feelings again and again. The researchers therefore scoured clinical trials for an approved substance that interfered with the brain chemistry in that area.

The team found that when cocaine-dependent mice were given a dose of a certain molecule called PD325901, they acted as if they had never been addicted or ever taken it at all, because the pathways in the brain that associated pleasure with drug use had been blocked.

"We collected all available molecules which block this pathway, awaiting clinical trial, and we tested them in animal models for cocaine addiction," lead researcher Professor Riccardo Brambilla told Business Insider. "We found one molecule which actually does the job very nicely."

The treatment also appeared to not interfere with general memory function of the animals, which Professor Brambilla points out would be a major side effect in human studies.

"Obviously patients who are people might make the situation slightly more complex," he said. "If we have a protocol for patients where we only administer the drug once or twice, it would minimise the potential side effects."

Cocaine addiction is a relatively narrow problem, affecting 2-3% of the general population in the UK, but Professor Brambilla and his team are now looking into the effect of their molecule on legal drugs such as alcohol and nicotine.