Addiction to Heroin and Morphine Can be Blocked, Rodent Study Suggests

Addiction to heroin and morphine can be blocked, suggests a new study conducted in rodents. The study revealed a key mechanism in the immune system that amplifies addiction to opioids.

Researchers found an immune receptor in the brain that stimulates the reward response to heroin and morphine, which makes opioids addictive, according to Bloomberg News. It may be possible to prevent dependence on the drugs by blocking the immune receptor, while increasing the medical benefits of the drugs for pain relief, the researchers report. Their findings are scheduled to be published this week in the Journal of Neuroscience.

The rats and mice in the study were given a drug called plus-naloxone, a variant of the drug Narcan, which is given to patients to counter opioid overdoses.

“Our studies have shown conclusively that we can block addiction via the immune system of the brain, without targeting the brain’s wiring,” researcher Mark Hutchinson of the University of Adelaide in South Australia said in a news release. “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 cravings for opioid drugs.”

He told Bloomberg News that human studies that will combine plus-naloxone with drugs such as morphine to prevent opioid addiction could start in 18 months. He said the results could eventually lead to new drugs that help patients with severe pain, as well as treat heroin addiction.