The Food and Drug Administration announced yesterday that it wants Endo Pharmaceuticals to take Opana ER, a tamper-proof, extended-release opioid medication, off the market.

"The abuse and manipulation of reformulated Opana ER by injection has resulted in a serious disease outbreak," Janet Woodcock, director of the FDA's Center for Drug Evaluation and Research, said in a statement released Thursday. "When we determined that the product had dangerous unintended consequences, we made a decision to request its withdrawal from the market."

It is a good thing Woodcock mentioned unintended consequences. Starting around 2010, pharmaceutical companies in the U.S. at the FDA's behest began releasing versions of their opioid drugs that users could not easily crush and then snort or inject. Back in the halcyon days of the opioid crisis, when more Americans were dying of car accidents than overdoses, crushing and snorting opioids was the most popular way to use them illicitly.

Introducing tamper-proofing was at the time considered a huge public health victory. "Some of the most widely abused drugs, including OxyContin, have been re-engineered in tamper-resistant formulations and introduced in place of their original versions," wrote former Sen. Tom Coburn and Scott Gottlieb, now the head of the FDA, in a 2012 post for the American Enterprise Institute. "Rates of abuse have fallen sharply as a consequence."

But while Gottlieb and Coburn were heralding tamper-proof formulations as a way to curtail non-medical use of opioids, users were busy figuring out other ways to get high. Some people simply chewed the tamper-proof pills. Some people figured out how to cook and inject them. Many people turned to heroin, which was suddenly cheaper than the newly patented tamper-proof formulations.

In 2015, researchers at the University of Toronto and Women's College Hospital in Toronto released findings that the tamper-proof model has not, and likely will not, solve the opioid problem. Yes, fewer patients were overdosing on tamper-proof medications, but "growing epidemiologic evidence shows that the introduction of tamper-resistant formulations has not lowered the rates of opioid-related deaths at a population level."

Why? Researchers found "increasing evidence that individuals shift to other opioids, including uncontrolled formulations such as heroin, when availability of prescription opioids changes."

(You don't need to read a study to know this. The internet is rich with first-person accounts from pill users, who–frustrated by the new formulations or cut off from their prescription by fearful doctors–turned to heroin.)

In the case of Opana ER, a tamper-proof version of which Endo brought to market in 2012, users who had previously snorted the drug took to injecting it. This phenomenon led to the largest HIV outbreak in Indiana's history, which then-Gov. Mike Pence initially addressed by praying.

That HIV outbreak, and related cases of Hepatitis C, are likely part of the "serious disease outbreak" Woodcock referenced in the FDA's press release. Left unmentioned is the likelihood that tamper-proofing has played a large role in the increased importation of fentanyl, a drug that is not just deadlier than heroin, but far deadlier than the crushable opioids that kicked off this current public health crisis.

Endo has the option to voluntarily remove Opana ER from the market. If the company declines, the FDA "intends to take steps to formally require its removal by withdrawing approval."

Until that happens, the FDA says it "is making health care professionals and others aware of the particularly serious risks associated with the abuse of this product."