Fentanyl is now the drug most frequently involved in overdose deaths in the U.S., according to a National Vital Statistics System report published Wednesday from the Centers for Disease Control and Prevention.

The report sheds a bright light on the changing nature of America's drug landscape – and the devastating number of overdose deaths that have occurred in the U.S. in recent years.

House Democratic Leader Nancy Pelosi has very likely sewn up the support she needs to become speaker of the House next year when the new Congress is sworn in.

In a deal struck with a group of House Democrats who had vowed to vote against the longtime Democratic leader in next month's House speaker election, the California lawmaker agreed to term limits that would see her hold the post through 2022 at the latest.

The agreement ensures Pelosi will easily have the 218 votes she needs to win the speakership on the House's first ballot.

The Vatican announced Wednesday that two cardinals have been let go from a papal council, the day after one of them was reportedly convicted of sexual abuse by an Australian court.

Open enrollment for health insurance coverage under the Affordable Care Act ends this Saturday.

The Arctic has experienced the "most unprecedented transition in history" in terms of warming temperatures and melting ice, and those changes may be the cause of extreme weather around the globe, according to the National Oceanic and Atmospheric Administration's 2018 Arctic Report Card.

Updated at 7:20 p.m. ET

Congressional negotiators have reached an agreement to overhaul the system for handling accusations of sexual misconduct against members, including a requirement that members pay out of pocket for some settlements and court judgments.