In 2013, nearly 9 billion pills containing hydrocodone were produced for prescription purposes. Other opioids added to the supply. Although this was several years ago and opioid production quotas have significantly reduced the supply of opioids, leftover pills are still a potential problem. Of those that are prescribed after surgery, more than 40% percent go unused.

Opioid drugs lose only about 1 percent of their potency per year. This means prescription opioids have a half-life of more than 50 years. These potent medications can remain viable (or toxic) for nearly a lifetime.

At any given time, billions of opioid pills that still retain their potency are available for diversion and non-medical use. That is a problem.

Conflicting Information About Safe Disposal

A public education campaign may convince some people who are reluctant to give up their extra medication that it would be better for society if they get rid of the drugs. However, even if people were persuaded to dispose of their unused medication, they may not know how to do so safely.

A recent report by Time suggests that even pharmacists do not know how patients should dispose of their leftover drugs. Of 900 pharmacists surveyed, only 23 percent correctly told callers how to safely dispose of opioids according to FDA guidelines.

The pharmacists' confusion is understandable. Various authorities have delivered different messages over the years about the best way to dispose of unused drugs.

The FDA recognizes that there are environmental concerns about flushing medicines down the toilet. However, the agency also believes that the risks associated with narcotic medicine outweigh any potential risks associated with flushing. The FDA includes hydrocodone, oxycodone, methadone and other opioids on a lengthy list of medicines that should be flushed down a toilet if no other safe disposal options are available.

The FDA even recommends flushing unused fentanyl lozenges (ACTIQ). The disposal instructions are very complicated. They require both a pair of scissors and wire-cutting pliers, and are roughly as convoluted as Walter White's method of making crystal meth in television's "Breaking Bad." I suspect that not everyone who is prescribed ACTIQ would be willing or able to follow all of those steps.

Evidently, the FDA believes that the risk of harm from overdose is greater than the danger the drugs present to the environment and to our water supply.

The Time story cites a 2017 U.S. Geological Survey and EPA report that found hundreds of drugs, including prescription opioids, in 38 streams across the country.

“Many of the drugs identified in the 2017 study are known to kill, harm the health of, or change the behavior of fish, insects and other wildlife. This, in turn, can impact the food chain, and eventually harm humans as well,” Time reported.

The FDA’s guidance on how to safely dispose of drugs can be confusing. Some medication is flushable, while other leftover drugs should be put in a sealed container or plastic bag with an “unappealing substance such as dirt, cat litter, or used coffee grounds” before being thrown out in the trash.

Take Back Programs

Drug take-back programs are intended to reduce the supply of excess prescription opioids and destroy the pills in an ecologically safe way. The FDA has a list of permanent take-back sites where people can dispose of unused medication. The DEA also has Drug Take Back Days, temporary collection sites for the safe disposal of prescription drugs.

However, not all take-back programs collect controlled substances. And it is estimated that fewer than 2 percent of unused drugs are returned. Also, these take-back programs are costly to implement.

The messaging around disposal of pain medication is conflicting. In a perfect world, all unused medication would be easily disposed of without causing negative consequences to the environment or the community. Also ideally, people in pain would not have to worry they might not receive a prescription for medication if they need one. Unfortunately, neither of those propositions is true.

Lynn R. Webster, MD, is a vice president of scientific affairs for PRA Health Sciences and consults with the pharmaceutical industry. He is the author of the award-winning book, “The Painful Truth,” and co-producer of the documentary, “It Hurts Until You Die.” You can find Lynn on Twitter: @LynnRWebsterMD.

Opinions expressed are those of the author alone and do not reflect the views or policy of PRA Health Sciences.