The idea that abuse of prescription drugs is rampant is no longer a subject of debate, but rather one of fact.

Add to that fact that another serious problem with patients prescribed opioids is that they now take them in combination with other drugs that don’t mix well with the powerful painkillers.

A study by Madison, New Jersey-based Quest Diagnostics, the lab data company, found that more than half of those who take opioid medications do so in “ways that put their health at risk,” either because they showed evidence of an unsafe combination of drugs or they showed that the patient was skipping doses.

Fifty-four percent of the more than 3.1 million physician-ordered tests that the firm analyzed from 2015 showed evidence of misuse.

And yet, there’s good news. The multiyear analysis found that test results from 2011 showed a misuse rate of 64 percent. So things are apparently getting better.

Except they’re not getting better in every regard. Among patients flagged as misusers, the percentage that were taking drugs that had not been prescribed by doctors had increased, from 32 percent in 2011 to 45 percent in 2015. Interestingly, the percentage only really jumped last year — it had only slightly increased in the four preceding years.

One of the most common issues is people who are prescribed opioids and continue to take sedatives. Mixing the two can produce potentially fatal complications. 

Health and treatment advocates have been pleading with the government and the medical community in recent years to take big steps, in terms of regulation and culture, to prevent abuse and misuse of opioids. In addition to urging physicians to more carefully scrutinize requests for opioid prescriptions, advocates have said that medical professionals must more carefully educate patients on how to take the medications safely.

Doctors have clearly responded. Opioid prescriptions have fallen in each of the last three years after steadily rising for two decades. Medical authorities, such as the Centers for Disease Control, have recommended a narrower set of conditions for which opioids can be prescribed, and they have also cautioned doctors to consider the risks of abuse and addiction when deciding whether to issue a prescription or — perhaps more importantly — when deciding whether to renew one.

“The culture is changing,” Dr. Bruce Psaty, a drug safety researcher at the University of Washington in Seattle, told The New York Times in May.

Dr. Harvey W. Kaufman, a co-author of the Quest study, said in a statement accompanying the report that improvements were coming, but not fast enough.

"The CDC's recent recommendations to physicians to carefully weigh the risks and benefits of opioid drug therapy are a step in the right direction, but clearly more needs to be done to address this public health crisis,” he says.