Just last month, the federal government was moving to ban a drug that you’ve probably never heard of: kratom. But in an unprecedented move, the US Drug Enforcement Administration (DEA) has changed its mind — the agency plans to publish a proposed rule on Thursday that will instead solicit public feedback on what to do with the drug.

The move is not totally surprising. Shortly after the DEA posted its initial declaration that it will ban kratom, it admitted that it had received an unusual amount of public backlash. "That was eye-opening for me personally," DEA spokesperson Melvin Patterson told the Washington Post. "I want the kratom community to know that the DEA does hear them. Our goal is to make sure this is available to all of them."

But the take-back is unusual for the DEA. Throughout America’s war on drugs, the DEA has leaned on the aggressive — usually moving quite quickly to ban drugs when it perceives any chance of public risk. In the case of kratom, the DEA will instead solicit feedback until December 1 to give the public and interested parties time to speak up about whether kratom should be banned or otherwise regulated.

The DEA previously explained that its initial move to ban the drug was largely an act of caution. As it stands, we simply don’t have much research on kratom — not its recreational use, nor its medical use. The DEA, in an abundance of caution after reports of rising use recently, moved to ban the drug for two years while it figured out how kratom works and the proper permanent regulatory classification for it.

The move, however, angered pain patients, some of whom were already getting the drug over online retailers. As the opioid painkiller and heroin epidemic kills tens of thousands of Americans each year, some pain patients have turned to alternatives to opioids to ease their pain without as big of a risk of addiction and overdose. One of those alternatives is kratom, which appears to have — although, again, we don’t know for sure, since the research is scarce — fewer deadly risks than opioids, yet can still relieve people’s pain.

This is the issue at hand: The DEA said there’s not enough evidence to legally allow widespread public consumption. But people who have used the drug for years say a ban would leave them out to dry, forced to suffer in pain, illegally buy kratom, or turn to more dangerous drugs, like opioid painkillers, for relief.

Before we get into all of that, though, it’s important to understand kratom — a drug that is relatively new to Americans, but has a long history in Southeast Asia.

Kratom is not a new drug

Kratom has been used in Southeast Asia for centuries, in part acting as an energy boost much like coffee does for Americans and coca leaves do for many people in northwest parts of South America.

The Transnational Institute, a research and advocacy group, reported in 2011 that kratom "is chewed in teashops, at certain ceremonies (though this practice is fading), and other informal social events, as well as while engaging in manual labor and in the comfort of one’s own home. Eating kratom is a tradition that has been practiced for centuries in southern Thailand and up to 70 percent of the male population in some districts use kratom daily. Indeed, many people in southern Thailand consider chewing kratom similar to drinking coffee."

The best overview of kratom’s effects comes from a 2015 study published in the Journal of Psychoactive Drugs. The study noted that there wasn’t rigorous scientific research on kratom’s effects on humans. So it instead analyzed hundreds of anecdotal accounts from Erowid, a popular website for drug users and researchers, to gauge its effects.

The study found several positive effects (from most to least common): euphoria, relaxation, enhanced sociability, increased energy, pain relief, sensory enhancement, and warmth or tingling. It also found some negative effects (from most to least common): nausea and stomachaches, withdrawal (from addiction), chills and sweats, dizziness and unsteadiness, vomiting, hangovers, and itching. Reviewing other research, the study found no good evidence that kratom alone has caused deadly overdoses.

According to the study, the pain relief element has become particularly promising for pain patients who want to seek alternatives to highly addictive, potentially deadly opioid painkillers. The study also found that kratom may aid with easing withdrawal from opioid addiction.

The Transnational Institute, in its 2011 report, noted these benefits have been known in other parts of the world for a long time:

Many studies report that the effect of kratom on the body reduces pain from withdrawal symptoms and helps manage detoxification. Interviews with [Thai] community members and leaders indicated that many people have been using kratom to wean themselves off heroin, yaba, and even alcohol and tobacco dependence. Indeed, 60 years ago, when kratom became a controlled substance in Thailand, its potential for management of opiate dependence had been widely recognised.

But how do the positives and negatives of kratom compare to opioid painkillers and other drugs? Chris Ingraham, who’s done a lot of great reporting on kratom at the Washington Post, scoured Erowid for positive and negative anecdotal accounts for several drugs and how they compared to the positive and negative accounts for kratom. He put them all together in this chart, which suggests that kratom is less risky than marijuana and the opioid painkiller oxycodone:

Now, this isn’t a scientific ranking, since it’s based on the anecdotal accounts of drug users on Erowid who are most likely using these drugs for recreational purposes.

Still, the ranking suggests kratom is relatively safe. So why did the DEA move to ban it?

Why the DEA moved to ban kratom

The DEA’s initial decision to ban kratom came as the drug had slowly gained some popularity in the US.

With that popularity came more negative reports of kratom abuse: The Centers for Disease Control and Prevention reported that the number of calls involving kratom to US poison centers "increased tenfold from 26 in 2010 to 263 in 2015." And the DEA has tracked 15 deaths linked to kratom between 2014 and 2016 — although none of those deaths were directly attributed to kratom, since people often use it with other drugs.

Given these concerns, the DEA at first concluded that it needed to ban kratom to "avoid an imminent hazard to the public safety." So it moved to classify kratom as schedule 1 — meaning the agency would consider kratom to have high potential for abuse and no recognized medical value, and banning its sales and production. (As of now, kratom is on the DEA’s list of "drugs of concern," meaning the agency is keeping an eye on the drug but not officially banning it.)

The DEA at first concluded that it needed to ban kratom to "avoid an imminent hazard to the public safety"

But the biggest issue for the DEA seemed to be that we just don’t know enough about kratom.

Generally, in the US, drugs are regulated to ensure their safety and effectiveness. The DEA’s mission is in large part to ensure that drugs are not being abused recreationally, but also to ensure that drugs that are often abused recreationally are available for use as medicine if there’s research to support medical use. It typically does this by locking drugs into different schedules that measure potential for abuse and medical value.

The rub here is the research: Large-scale clinical trials — the kinds the Food and Drug Administration requires for traditional medicines — are typically necessary to prove illicit drugs have medical value. Once these trials show that, for example, kratom can be used safely and effectively as medicine, it can be classified as schedule 2, 3, 4, or 5, the schedules of drugs that have high to low levels of abuse and some medical value. (Schedule 1 is the only classification for drugs that have no recognized medical value, which is how you end up with marijuana and heroin in the same schedule 1 category.)

This research could help answer some of the big questions surrounding kratom: How well does it relieve pain, and how well does that pain relief hold up as long-term users build tolerance? Can kratom cause deadly overdoses by itself? How addictive is it? What are the short-term and long-term effects, good or bad, we don’t know about? Does kratom affect most people in the same way, or can it only benefit a certain segment of the population?

With the federal government’s ban, there’s a real concern that the research on kratom could remain stagnant

Until that research is done, kratom doesn’t have enough evidence, based on the scheduling system, to support its medical efficacy and safety. So the DEA wanted to classify it as schedule 1 as researchers studied the drug.

But sometimes the process doesn’t work. We see this with marijuana: Patients have reported that pot helps them with varying medical conditions for at least decades. Yet the government has been slow to allow and fund research in large part due to its view, made official by marijuana’s schedule 1 classification, that pot has no medical value. The result is we have some studies that show it can relieve pain and can potentially substitute far deadlier opioid painkillers for some pain patients — but we don’t have research large and rigorous enough to get marijuana officially approved as medicine by the DEA.

There’s already a dearth of research on kratom. With the federal government’s ban, there was a very real concern that the research on kratom could remain stagnant — just like it has for marijuana.

The DEA didn’t seem to think this would happen. Patterson, the agency’s spokesperson, told the Post that he doesn’t "see it being schedule 2 [or higher] because that would be a drug that’s highly addictive." He added, "Kratom’s at a point where it needs to be recognized as medicine. I think that we are going to find out that probably it does."

Still, the DEA’s move terrified kratom users. The American Kratom Association described the DEA’s proposed ban in very grim terms:

TAKE ACTION TO SAVE KRATOM NOW!!! We are now facing our darkest hour. The DEA has filed a notice of intent to schedule and ban kratom by September 30th, 2016. Countless people depend on this safe and effective herbal remedy related to coffee that was sacred to the Buddhists, who have used it safely for thousands of years. Many of you depend on this healing leaf for your general well-being, pain and suffering, depression, anxiety, PTSD, opioid dependency, and more.

There was good reason for the sense of urgency: As the opioid epidemic kills tens of thousands of Americans each year, many people are scared they’re going to lose a relatively safe alternative to opioid painkillers if the kratom ban takes effect.

The DEA apparently took those concerns seriously enough to withdraw its proposed ban — at least until it gets public feedback.

Kratom could help deal with the opioid painkiller and heroin epidemic

The timing of the DEA’s move was particularly concerning to kratom advocates because the country is currently mired in a huge public health crisis — the opioid painkiller and heroin epidemic — that kratom could help fight.

Here’s the quick summary of the opioid epidemic: In the 1990s, doctors were under enormous pressure to treat pain as a serious medical issue — with good reason, as roughly one-third of Americans suffer from chronic pain, according to a 2011 report from the Institute of Medicine. As pharmaceutical companies pushed the drugs through an aggressive, dangerously misleading marketing campaign, doctors prescribed excessive numbers of opioid painkillers — getting a lot of people hooked on the drugs and letting excess painkillers flood the black market. Opioid painkiller overdoses steadily increased, reaching epidemic levels by the 2010s.

Over time, these opioid users developed a tolerance and sought a better high. They turned to heroin, which has long been cheaper, more potent, and — especially after the government crackdown on painkillers to fight addiction — more available than opioid painkillers. As a result, heroin deaths rose. (A 2015 analysis from the Centers for Disease Control and Prevention found that people who are addicted to prescription painkillers are 40 times more likely to be addicted to heroin.)

With heavy emphasis on the fact the research on kratom is by no means conclusive, it seems kratom could help mitigate this epidemic by substituting opioid painkillers for some pain patients. Since kratom doesn’t appear to cause deadly overdoses frequently or at all while opioid painkillers do, replacing opioids with kratom could prove a public health gain. And since kratom doesn’t appear to cause the kind of addiction that leads to heroin use, it could also stop people from getting on a pathway to a much more dangerous, deadlier drug.

But if the DEA shut down legal supplies of kratom, pain patients would no longer be able to legally access the drug. If that forced them to turn to opioid painkillers or, worse, heroin, that could be a horrible outcome for public health.

The DEA had good reason under the current legal framework to act in this way — as noted above, there’s just not enough research to determine kratom’s full medical efficacy and safety. But kratom’s potential and the ongoing threat of the opioid epidemic suggest that the current legal framework is perhaps too inflexible for a world with bigger, more pressing public health crises than a drug that’s not even proven to be unsafe. The DEA, for its part, now seems to recognize that — so it will let the public speak before it takes further action on the drug.