A new study finds methadone and buprenorphine are highly effective in treating opioid use disorder and reducing overdoses, but these treatments are underused by physicians.

Researchers compared various approaches to dealing with opioid use disorder: the use of methadone and buprenorphine; no treatment; inpatient detoxification or residential services; intensive outpatient or partial hospitalization; naltrexone; and outpatient counseling.

The researchers found only treatment with buprenorphine or methadone led to significant decreases in overdoses and emergency department visits or hospitalizations at three and 12 months of follow-up, The Pew Charitable Trusts reports.

The study found only a small number of people can access these treatments, largely because of lack of access to doctors authorized to prescribe the medications, high co-payments, prior authorization requirements and other restrictions on use.