The commissioner of the FDA called on Congress to empower the agency to better police compounding pharmacies like the one at the center of a national meningitis outbreak. But Republican lawmakers pushed back, arguing that the agency has enough authority, leaving it unclear whether the House would support efforts to increase oversight. In the hearing, commissioner for the House Committee on Energy and Commerce, Dr. Margaret Hamburg, testified that a tangle of conflicting court decisions and the lack of a clear definition of compounding in the law had limited the agency's ability to build a case against compounding pharmacies that fail to meet basic safety standards. The central question is whether the FDA has enough power to crack down on large-scale compounding companies that mix medicines for individual patients.