ATLANTA (July 3, 2012)--Methadone is involved in nearly one-third of deaths from prescription painkillers, but overdose deaths from methadone appear to have peaked, the U.S. Centers for Disease Control and Prevention said Tuesday.

Methadone is known mainly for treating heroin addictions, but it is also prescribed for pain.

Health officials say most of the overdose deaths occur in people who take it for pain and not in heroin addicts.

New federal data show the number and rate of methadone-related deaths have fallen since 2007.

Experts believe doctors are more cautious today about prescribing methadone for pain because of federal warnings and state prescription monitoring programs.