The true cost of the opioid drug epidemic in the US was a staggering $504bn (£380bn) in 2015, the White House has said.

In an analysis released on Monday (20 November), the Council of Economic Advisers (CEA) says the figure is six times larger than the most recent estimate.

The council said a private study last year estimated that prescription opioid overdoes, abuse and dependence in the US in 2013 cost $78.5bn.

Most of that was attributed to health care and criminal justice spending, along with lost productivity.

The council said its estimate is significantly larger because the epidemic has worsened, with overdose deaths doubling in the past decade. Also, some previous studies didn't reflect the number of fatalities blamed on opioids, a powerful but addictive category of painkillers.

The council also noted that previous studies had focused exclusively on prescription opioids, while its study also factors in illicit opioids including heroin.

"Previous estimates of the economic cost of the opioid crisis greatly underestimate it by undervaluing the most important component of the loss — fatalities resulting from overdoses," said the report.

It comes after President Donald Trump last month declared opioid abuse a national public health emergency.

He announced an advertising campaign to combat what he said is the worst drug crisis in the nation's history, but he did not direct any new federal funding toward the effort.

Trump's comments stopped short of the emergency declaration that had been sought by a federal commission the president created to study the problem.

An interim report by the commission argued for an emergency declaration, saying it would free up additional money and resources.

But in its final report earlier this month, the panel called only for more drug courts, more training for doctors and penalties for insurers that dodge covering addiction treatment.

More than 64,000 Americans died from drug overdoses last year, mostly from either a prescription painkiller or an illicit opioid like heroin.

"This is the first but not the last publication CEA plans to issue on the opioid crisis to provide policymakers with the economic analysis needed to review and assess potential policy options," the CEA study said.

"A better understanding of the economic causes contributing to the crisis is crucial for evaluating the success of various interventions to combat it."

Opioid sales deaths US
Opioid deaths correlate strongly with opioid prescriptions Annual Review of Public Health