Brennan's spokesman David Partenheimer said in a statement this week that his agency is "working with the senator to address this issue and will respond directly to her office."
Mailing quirk has Missouri residents with Iowa addresses →
"However, we share the senator's goals of keeping dangerous drugs out of the hands of the American public and maintaining the safety of our nation's mail system," spokesman David Partenheimer said.
Sen. Rob Portman targets synthetic opioids in U.S. mail →