Sydney: In a major breakthrough, scientists have shown that it is possible to block addiction to morphine and heroin, while boosting relief from pain.
A team from the universities of Adelaide (Australia) and Colorado (US) has discovered the key mechanism in our immune system that amplifies addiction to opioids, which have pain-killing effects.
Opioids are among the world`s oldest known drugs. The use of the opium poppy for therapeutic benefits predates recorded history.
Lab studies have shown the drug naloxone will selectively block the immune-addiction response.
The results could eventually lead to new co-formulated drugs that assist patients with severe pain, as well as helping heroin users to kick the habit, the Journal of Neuroscience reports.
"Our studies have shown conclusively that we can block addiction via the immune system of the brain without targeting the brain`s wiring," says Mark Hutchinson, research fellow in the Adelaide`s School of Medical Sciences, who led the study, according to an Adelaide statement.
"Both the central nervous system and the immune system play important roles in creating addiction. But our studies have shown we only need to block the immune response in the brain to prevent craving for opioid drugs," says Hutchinson.
"The drug naloxone automatically shuts down addiction. It shuts down the need to take opioids. It cuts out behaviours associated with addiction, and the neurochemistry in the brain changes -- dopamine, which is the chemical important for providing that sense of `reward` from the drug, is no longer produced," says Hutchinson.
Linda Watkins, professor and study co-author from the Centre for Neuroscience at the University of Colorado Boulder, says: "This work fundamentally changes what we understand about opioids, reward and addiction."