Advocates of a stronger response are incredulous.  “I’m shocked that Congress and the president would constrain D.E.A. from taking on corporate drug dealers in the midst of the worst addiction epidemic in U.S. history,” said Dr. Andrew Kolodny, the director of Physicians for Responsible Opioid Prescribing and an addiction specialist. “This law allows opioid distributors to reap enormous profits and operate with impunity at the public’s expense.”  Congress’s actions have sought to balance the conflicting demands of deep-pocketed chain pharmacies such as CVS and Walgreens and drug distribution companies like Cardinal Health and McKesson with the victims of an epidemic that has ravaged some of the poorest parts of the country — but also some of the most politically sensitive, like Ohio and New Hampshire.  Chain pharmacies and drug distributors say their businesses have been disrupted and profits hurt by D.E.A. investigators who have ordered immediate closures of pharmacies deemed regional destinations for addicts seeking a fix.  “The D.E.A. has employed the same disrupt-and-dismantle tactics to take down international drug cartels and other criminals as it does to combat prescription drug abuse,” said John Gray, the president of the Healthcare Distribution Management Association, a trade organization for drug wholesalers.  But past and present agency officials complain that they were steamrollered by a powerful lobby.  “Under this law, the bad actors simply have to promise to be good, and we won’t take them to court to punish them for what they’ve already done,” said Joseph T. Rannazzisi, who retired in October after 11 years of directing the D.E.A.’s office of diversion control. “It’s obvious that industry had a very strong hand in crafting this bill.”  To its sponsors, the new law is an uncontroversial clarification of when the right to distribute controlled substances can be suspended or revoked, a matter separate from the opioid addiction fight. It also establishes a process for federal agencies to go through in many cases before distribution centers can be shut down, giving them 30 days to rectify issues as they crop up in an attempt to reduce disruptions to patients.  Written by Representatives Tom Marino, Republican of Pennsylvania, and Peter Welch, Democrat of Vermont, it passed the House in April by unanimous consent, a month after the Senate approved its version without objection. The Senate measure was equally bipartisan, drafted by Senator Orrin G. Hatch, a conservative Republican from Utah, and Senator Sheldon Whitehouse, a liberal Democrat from Rhode Island.  “The D.E.A. has a big job,” Mr. Welch said. “I’d like to see them not having to waste their time on protocol issues with distribution centers, because that’s not where the problem exists.”  In a statement, Mr. Marino said, “Until now, clear comprehensive legislation that protected patients’ right to access necessary medication while stopping those who might abuse such drugs did not exist.”  For all the self-congratulations over a recent rash of opioid abuse bills — the House passed 18 measures last week after the Senate’s comprehensive version in March — Congress has yet to send a treatment measure to the president.  And lawmakers are steeling themselves for the real fight: how to pay for it. The issue has become a surprisingly potent one, with some vulnerable Senate Republicans running for re-election on their efforts to fight addiction and siding with Democrats in their chamber over House Republicans to make their point.  Senator Rob Portman, Republican of Ohio and a sponsor of the Senate bill, said his version was superior to the House’s in two areas: addiction prevention and new sources of funding that do not siphon money from other programs.  And because many opioid addicts begin with prescription drugs, he said, Congress needs to approve some restrictions on who can write and fill prescriptions. The “one doctor, one pharmacy” provision in the Senate bill would cut down on doctor shopping and could counter any ill effects of curbing the D.E.A.’s enforcement power.  “That’s really narrowing your choices to people who know you, know what you need,” he said.  Trying to strike a balance between access for the needy and restrictions to prevent abuse has bedeviled the fight against the opioid crisis since its beginnings. But as the annual death toll from the epidemic soared, those calling for greater restrictions seemed to have gained the upper hand, with new guidelines from the C.D.C. and greater restrictions on popular narcotics finalized by the Food and Drug Administration.  The one law that has been enacted, called Ensuring Patient Access and Effective Drug Enforcement Act of 2016, gives those arguing for greater access to these medications an unlikely lift.  “It’s a significant blow to D.E.A.’s enforcement authority, and that doesn’t make any sense to us,” said Carmen Catizone, the executive director of the National Association of Boards of Pharmacy.  As the lead agency in prosecuting a drug war that liberal and conservative politicians see as flawed, the D.E.A. has lost clout. The agency’s growing efforts to combat opioid abuse have also meant clashes with the powerful lobbies of drug makers and pharmacists.  On Capitol Hill, Mr. Rannassizi became a symbol of the D.E.A.’s recalcitrance, particularly after he suggested that lawmakers would be “supporting criminals” if they passed the measure.  “This offends me immensely,” Mr. Marino, a former prosecutor, responded to Mr. Rannassizi at a 2014 hearing on an earlier version of the legislation.  By passing the law, “Congress is sending the D.E.A. a message,” Mr. Marino said to the agency’s administrator, Michele M. Leonhart. “You should take a serious look at your regulatory culture and seek collaboration with legitimate companies that want to do the right thing.”
The House and the Senate have whipsawed between ensuring access to narcotic painkillers and addressing the addiction epidemic linked to those drugs.