A Democratic senator is blocking President Barack Obama's nominee to head the U.S. Food and Drug Administration.
Massachusetts Sen. Edward Markey says in a statement that he's put a hold on Dr. Robert Califf's nomination.
Markey wants the agency to be tougher on abuse of opioid painkillers.
The Centers for Disease Control and Prevention says deaths linked to misuse and abuse of prescription painkillers climbed to 19,000 last year, the highest on record. By its estimation, deaths tied to these drugs have risen more than four-fold since 1999 amid increased prescribing by U.S. doctors.
Califf is the No. 2 official at the agency. He was a prominent cardiologist and medical researcher at Duke University for more than 30 years.