A new government report finds 40% of U.S. counties didn’t have a single healthcare provider approved to prescribe the opioid addiction medication buprenorphine in 2018.

Healthcare providers must receive a government waiver in order to prescribe buprenorphine as an opioid addiction treatment. Almost 47,000 healthcare providers received waivers from the federal government in 2018 to prescribe buprenorphine. The Inspector General report found providers with a waiver were not necessarily found in the areas where access to medication-assisted treatment is most critical.

Among the approximately 1,100 counties identified by the report as having the greatest need for buprenorphine, 56% likely had inadequate capacity to treat patients with the medication in an office setting.

Ann Maxwell, who oversaw production of the report, told Reuters that in some communities, addiction treatment efforts focus on abstinence instead of medication-assisted treatment. “Medication-assisted treatment has been found to be more effective than abstinence-based treatment at keeping patients in treatment and reducing their use of opioids because (these) drugs are designed to reduce opioid cravings and withdrawal,” she said.