Addiction treatment advocates are trying to convince Republican legislators in states greatly impacted by the opioid epidemic to protect insurance coverage for substance abuse treatment if the Affordable Care Act (ACA) is repealed.

Repealing the ACA without having a plan in place to preserve coverage would weaken efforts to address the opioid crisis, according to Gary Mendell, founder of Shatterproof, a nonprofit that advocates for legislation to fight addiction. Shatterproof is working with the National Council for Behavioral Health, which represents 2,800 providers of mental health and addiction treatment, The Wall Street Journal reports.

The groups are focusing on legislators in West Virginia, Maine, Pennsylvania, Tennessee, Ohio, Nevada, Alaska and Arizona.