Junkie clean-up

Heroin addicts may soon be treated with a polymer implant instead of taking a daily dose of the heroin substitute, methadone. Researchers at John Hopkins School of Medicine in Baltimore, USA, have developed a button-sized implant that releases a steady stream of hydromorphone for up to three months. Hydromorphone, like methadone, blocks opiate receptors in the brain that bind to heroin, thereby eliminating cravings and withdrawal symptoms. Heroin addicts have to take a dose of methadone every day. The methadone released by the implanted polymer gradually -- over a period of one to three months -- decreases the user's dependency on heroin and other opiates.