Is Ketamine an Opioid?

By Pat Anson, PNN Editor

A drug used to treat depression and pain is being touted as possible solution to the opioid crisis.

This week a South Carolina drug maker said it would partner with a medical device company to sell ketamine in take home medication bags that can be administered by an ambulatory pain pump. The idea is to give patients recovering from surgery a safer alternative to opioids.

“We are proud to partner with InfuTronix Solutions to deliver opioid-free pain medication to patients across the country,” Nephron Pharmaceuticals CEO Lou Kennedy said in a statement. “The overuse of opioids is a crisis in America. Non-narcotic pain management is a cost-saving way that companies like ours can help save lives.”

Non-narcotic? Opioid-free?

That’s not what a team of researchers at Stanford University concluded last year after studying how ketamine works in the brain. In a small clinical study, they gave a dozen patients diagnosed with depression a combination of ketamine and naltrexone – an opioid-receptor blocker. To their surprise, naltrexone stopped ketamine from working as an antidepressant.

In effect, the researchers discovered that ketamine works just like oxycodone, hydrocodone and other painkillers – by activating opioid receptors in the brain. 

“Everything that I was taught, and everything that I’ve always taught my students — all of the evidence supports the fact that ketamine is not an opioid,” said lead author Boris Heifets, MD, a clinical assistant professor of anesthesiology, perioperative and pain medicine. “I was really surprised at the results.”

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“And the results were so clear that we ended the study early to avoid exposing additional patients to the ineffective combination treatment,” said co-lead author Nolan Williams, MD, a clinical assistant professor of psychiatry and behavioral science.

The Stanford research, published in The American Journal of Psychiatry, caught psychiatrists and pain management experts by surprise. Some urged caution about the long-term use of ketamine until more can be learned about potential side effects such as addiction. Some depressed patients taken off ketamine have shown signs of withdrawal and became suicidal.

“Given the rapid relapse and potential suicide risk, it is hard to know what to recommend to clinicians. Should they really continue to use the agent beyond an acute course? For how long? In whom?” Alan Schatzberg, MD, a Stanford professor of psychiatry and behavioral sciences, warned in a commentary. “The drug’s opioid properties need to be considered when considering how best to use it.”

‘A Black Eye to Ketamine’

Talk like that has given ketamine a bad rap, according to experts at Johns Hopkins University School of Medicine. They’ve published a commentary of their own, defending the use of ketamine as a necessary treatment for depression that doesn’t respond to typical antidepressants.

“A (Stanford) study done late last year delivered a black eye to ketamine, and as a result of the coverage, there was a wholesale acceptance by both potential patients and physicians that ketamine is an opioid,” says Adam Kaplin, MD, an assistant professor of psychiatry and behavioral sciences at Johns Hopkins.

“This is most worrisome if people continue to think this way, particularly in the wake of the opioid epidemic; clinicians won’t refer patients for a treatment, despite that it has been shown to be incredibly effective for many patients with treatment-resistant depression.”

Kaplin says there is ample evidence that ketamine sticks to NMDA receptors in the brain that are involved in learning and memory. Because these NMDA receptors are found together with opioid receptors, Kaplin says it’s no surprise that the can meddle with one another, like interference picked up on a phone call or static on the radio.

“This interference and cross-talk does not mean that ketamine is an opioid, and to wrongly label it as such could eventually keep patients from essential antidepressant medications that could make a huge difference in their quality of life,” said Kaplin, who plans on opening a ketamine clinic.

The debate over whether ketamine is an opioid comes at a time when its use is expanding.  Ketamine was approved by the FDA in 1970 solely as a surgical anesthetic to be taken intravenously or by injection. But a growing number of clinics now offer off-label infusions of ketamine to treat depression, post-traumatic stress disorder and difficult chronic pain conditions such as Complex Regional Pain Syndrome (CRPS).

Demand has grown so much there are reports of ketamine shortages. Although ketamine itself is inexpensive, the infusions can cost several hundred dollars and are not covered by insurance.

Ketamine Nasal Spray

Not until this year did the Food and Drug Administration approve the use of ketamine to treat depression, when it okayed a nasal spray (Spravato) made by Janssen Pharmaceuticals that contains a ketamine compound.

The FDA approved Spravato even though 2 out of 3 short term trials failed to prove its effectiveness. The spray was effective in a longer trial, but only when taken with a conventional antidepressant.

Because of the risk of abuse and side effects, Spravato can only be administered in a doctor’s office, where patients can be observed for two hours after taking a dose. A single dose will cost about $900.

The FDA has called the herbal supplement kratom an opioid because it acts on opioid receptors, but the agency has not taken that step with ketamine. Given current attitudes about opioids, it’s fair to say the FDA would have never approved Spravato if it was considered an opiate.

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In addition to its medical uses, ketamine is used as a recreational party drug – known as “Special K” -- because it can cause hallucinations and intense dream-like states.

Whether taken to get high or to treat pain and depression, it’s clear that ketamine is a potent drug that has both harms and benefits. And experts say it needs to be viewed with caution until we know with more certainty how it works.

“Unfortunately, when one approaches ketamine as another antidepressant rather than a drug of abuse, this type of trap is easy to fall into, and in the end, such mistakes can be catastrophic,” Schatzberg said in his commentary. “We have witnessed four decades of supposedly new and safer opioids that have turned out often to be, if anything, even more abusable and lethal."

Guideline Paranoia

By Carol Levy, PNN Columnist

I recently posted an article to an online chronic pain support group about the CDC’s opioid prescribing guideline.

“For treating acute pain, the guideline recommends a quantity no greater than what is needed for the expected duration of pain severe enough to require opioids, specifying that three days or less will often be sufficient and more than seven days will rarely be needed,” the guideline states.

It makes sense to me. And I assumed that would be the response my post would get. The recommendation is only for treating acute pain and acute pain shouldn’t need chronic, long term opioid treatment.

Instead, the replies were quick, angry and knee jerk:

“How dare they decide what and how many we need? This will hurt chronic pain patients.”

“They always come after us. These may be for acute pain patients, but you just know more draconian guidelines are just around the corner for chronic pain patients.”

The CDC guideline does not say, “And no one, even if their acute pain continues longer than 3 or 7 days, will be able to get the pain meds they need.” But that was how it was interpreted.

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And then the people replying went one step further: “Soon they will be writing guidelines that even those in chronic pain can only have opioids for a specified period of time and a specific dosage, and not one grain more or one day longer.”

I see this common response and reaction as a major issue. When any new guideline is proposed (and people forget these are guidelines, not absolutes), it is a major catastrophe: “They are coming after us.”

Too often we act in a way that appears akin to addictive behavior. We have to have our opioid medications. And any restriction, even when it is not related to chronic pain, is one restriction too many: “They are going to take away my drugs. Then what will I do?”

We seem to have lost the concept of consideration. No time is taken to think through the new suggestions. Instead it is an immediate jump to: “This will hurt me. I won't be able to get the meds I need.”

For many of us, opioid medication is all that is left or the only option. The idea that someone, especially the government, may rip them from us is truly terrifying.

But I wonder. Maybe if we did not take any and all new guidelines as a frontal attack on us, maybe we would not be seen and referenced so often as a major component and cause of the “opioid epidemic.”

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Carol Jay Levy has lived with trigeminal neuralgia, a chronic facial pain disorder, for over 30 years. She is the author of “A Pained Life, A Chronic Pain Journey.”  Carol is the moderator of the Facebook support group “Women in Pain Awareness.” Her blog “The Pained Life” can be found here.

The information in this column should not be considered as professional medical advice, diagnosis or treatment. It is for informational purposes only and represent the author’s opinions alone. It does not inherently express or reflect the views, opinions and/or positions of Pain News Network.

How Common Is Opioid Addiction?

By Roger Chriss, PNN Columnist

As the opioid crisis continues to worsen, there is increased scrutiny of both prescribing levels and fatal overdose rates. The goal of reducing opioid prescriptions is to decrease the exposure to opioids, on the theory that medical use of opioid analgesics is closely linked with addiction and overdose risk.

But how valid is that theory? A key issue in the crisis is opioid addiction rates, which can be divided into medical and non-medical addiction.

Medical Opioid Addiction Rates

The National Institute on Drug Abuse (NIDA) reports that 8 to 12% of patients on long-term opioid therapy develop an opioid use disorder.

“The best and most recent estimate of the percentage of patients who will develop an addiction after being prescribed an opioid analgesic for long-term management of their chronic pain stands at around 8 percent,” NIDA Director Nora Volkow, MD, told Opioid Watch.

The NIDA estimate is well-researched and widely accepted. But there are other estimates, each with important qualifications.

Cochrane found in a major review of studies of long term opioid therapy for non-cancer pain that only 0.27% of participants were at risk of opioid addiction, abuse or other serious side effects.

In another large study, The BMJ reported that only about 3% of previously opioid naïve patients (new to opioids) continued to use them more than 90 days after major elective surgery.

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Other addiction rates include numbers as low as 1% and as high as 40%. But details matter. Much of the difference in addiction rates stems from three factors:

  1. How well screened the patient population is

  2. How carefully monitored the patients are during opioid therapy

  3. How the criteria for opioid use disorder are applied

In other words, a well-screened and closely monitored population of adults with no risk factors may well have an addiction rate of 1%. The recent SPACE study by Erin Krebs, MD, in which over 100 people with knee osteoarthritis and low back pain were put on opioid therapy for a year, saw no signs of misuse, abuse or addiction. There were also no overdoses.

Non-Medical Opioid Addiction Rates

It’s also important to look at the percentage of people who become addicted to opioids without ever having an opioid prescription. Here the addiction rates are much higher.

A 2009 study in the American Journal of Psychiatry found that among treatment-seeking individuals who used OxyContin, 78% had not been prescribed the drug for any medical reason. The OxyContin was “most frequently obtained from nonmedical sources as part of a broader and longer-term pattern of multiple substance abuse.”  

The 2014 National Survey on Drug Use also found that about 75% of all opioid misuse starts outside medical care, with over half of opioid abusers reporting that the drugs were obtained “from a friend or relative for free.”

Heroin is considered highly addictive, with nearly one in four heroin users becoming dependent. Importantly, most people who try heroin already have extensive experience with other substances, including opioid medication, and many have serious mental illness. There is no research on the addictive potential of heroin in drug-naive people.

Relatively little is known about the complex and concealed world of nonmedical opioid use. Researchers like UCSF’s Daniel Cicerone are working to fill this gap by collecting information on overdoses to get a more accurate picture on the type of opioids being used.  

Risk Management

Opioids remain an essential part of modern medicine, from trauma and battlefield medicine to surgery, end-of-life care and long-term management of chronic, progressive degenerative conditions. This makes risk management vital.

Current tools to screen patients include the long-standing COMM tool and the new NIDA TAPS tool. Novel approaches using genetic testing for opioid risk may eventually help clinicians better assess risk, too. And improved data analytics may also help reduce addiction.

"Understanding the pooled effect of risk factors can help physicians develop effective and individualized pain management strategies with a lower risk of prolonged opioid use," says Ara Nazarian, PhD, a researcher at Beth Israel Deaconess Medical Center.

The Krebs SPACE study achieved an admirable level of safety by carefully screening and monitoring patients during opioid therapy. A similar patient-focused approach that acknowledges the low rate of medical opioid addiction and works to minimize it further is likely to bring benefits to both individuals and society at large.

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Roger Chriss lives with Ehlers Danlos syndrome and is a proud member of the Ehlers-Danlos Society. Roger is a technical consultant in Washington state, where he specializes in mathematics and research.

The information in this column should not be considered as professional medical advice, diagnosis or treatment. It is for informational purposes only and represents the author’s opinions alone. It does not inherently express or reflect the views, opinions and/or positions of Pain News Network.

Mayo Clinic: Opioid Prescribing Has Not Changed

By Pat Anson, Editor

Numerous studies have shown that opioid prescriptions are falling. The trend started in 2011 and appears to have accelerated since the release of the CDC’s 2016 opioid prescribing guidelines.

The volume of opioid medication filled last year fell by 12 percent, the largest decline in 25 years, according to the IQVIA Institute.  Prescriptions for hydrocodone – once the most widely prescribed drug in the country – have fallen by a third since their peak. Even the CDC has reported that opioid prescriptions have dropped by about 5% each year between 2012 and 2016.

Anecdotally, many patients tell us opioids are harder, if not impossible, to obtain. Nearly half of the 3,100 patients PNN surveyed last year said they were getting a lower dose. And one in four said they were no longer prescribed opioids.

But according to Mayo Clinic researchers, opioid prescribing hasn't changed that much and remains at high levels. In a study published in the British Medical Journal (BMJ), they report that opioid prescriptions for Medicare and privately insured patients have remained relatively stable over the past few years. And the average daily dose of opioids is well above what it was 10 years ago.

“If you’re hearing the message that prescription opioid use is starting to decline, I think we need to counter that message and say in most populations it really isn’t moving very much.” says lead author Molly Jeffery, PhD, scientific director of the Mayo Clinic Division of Emergency Medicine Research. “Our data suggest not much has changed in prescription opioid use since about five years ago.”

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Why the discrepancy? Jeffrey says most of the previous studies only looked at market-level data – the amount of opioids that drug makers reported producing and selling. She and her colleagues dug a little deeper, looking at insurance claims for 48 million U.S. patients between 2007 and 2016.  

Over that 10-year period, the rate of opioid use by privately insured patients remained relatively flat at 6 to 7 percent. The average daily dose for that group, about two pills of 5-milligram oxycodone, remained the same.

The rate of opioid use by Medicare patients 65 and older peaked at 15% in 2010 and decreased slightly to 14% by 2016. Their average daily dose, three 5 mg pills of oxycodone, also remained relatively unchanged.

Rates of opioid use by disabled Medicare patients also haven't changed much, peaking at 41% in 2013 and falling to 39% in 2016. Their average daily dose remains relatively high, about eight 5 mg oxycodone pills. 

“Our research of patient-level data doesn’t show the decline that was found in previous research,” says Jeffery. “We wanted to know how the declines were experienced by individual people. Did fewer people have opioid prescriptions? Did people taking opioids take less over time? When we looked at it that way, we found a different picture.”

The Mayo study includes an interesting disclaimer. While the researchers looked at data from patient insurance claims, they never surveyed or spoke to any patients about their opioid use. The researchers said they would “engage” with patients in future blog posts and press releases.

You can share your views with Molly Jeffery by email at jeffery.molly@mayo.edu or @mollyjeffery on Twitter.

I Have to Drive 6 Hours for Pain Care

By Bailey Parker, Guest Columnist

I feel so alone and isolated. There have been times I wanted to die, but my 5-year old son keeps me going. I get up every day for him.

About two years after he was born, I had a car wreck. I hit a coyote at 60 mph and ripped the radiator off my car. The doctors told me I had the spine of an 80-year old and needed a double level fusion in my neck.

I was 34 then and in tremendous amounts of pain. But after reading online stories in spine health forums, I was skeptical about the surgery. Everything told me to wait. So I did, for a year. I saw three surgeons and a neurologist. They all told me to have the surgery.

I live in a small city in southwest Colorado. When it comes to opioid pain medication, all the doctors here seem to have taken the stance, “We just don’t do that here.” The nearest city is Albuquerque, New Mexico, which means a 4-hour drive for me across state lines, or a 6-hour drive to Denver over mountain passes.

Before my surgery, one of the doctors of orthopedic medicine prescribed my pain medication. For two months, I was able to work again and was beginning to get back on my feet. I remember thinking at the time that I didn’t want to take medication for the rest of my life, but the fusion sounded worse.

The third month in I called for a refill of my medication. They told me no, but wouldn’t say why or give me a follow up exam with the doctor. He was too busy and couldn’t see me for a month. I waited one excruciating month and went to see him, asking what happened.

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He had looked at my prescription records and saw a prescription for narcotics from another doctor for when I had cystic fibroids on my ovaries. It was not the same pain medication as what he prescribed me, and I didn’t even know they were the same type of medicine.  

Even though I had a broken neck, he did not feel comfortable prescribing to me anymore. His office then took 6 months to get my medical records sent to my primary care doctor. I had to physically go in and yell at them that I was about to have major surgery. This was the first time I felt treated like an addict, but not the last.

I went to my primary care physician and explained what happened with this other doctor. We have a very good relationship. She knows all of my medical history. She handled my pain medication before my surgery but was very clear that she would not do it for an extended period.

I never take more medication than prescribed. I am not an addict. I do everything they tell me. I was walking and doing yoga every day, just as the doctors recommended. I took my vitamins and a fruit shake every day.

After the fusion surgery, things just didn’t feel right. I was in tremendous pain again and this time there was more of it in different places. I told the physician’s assistant at my surgeon’s office and he told me to just get off all the drugs. He said it would help. He told me I would be fine. I wasn’t.

I struggled for another month before I demanded to see the surgeon. He told me I would benefit from OxyContin and gave me a week’s supply. For the first time since my accident, I was able to work and properly care for my son. My depression lifted. But when I called to tell them that I was doing good on the medication, they said it was time to go back to my primary care doctor and any further medication would have to be prescribed by her.

I went to see her, but she still did not feel comfortable handling my care and referred me to a pain clinic 6 hours away. I was in despair, thinking that I had crippled myself for life and would lose my job, my son and my husband. All of these relationships were strained at this point.

The pain clinic helped me get my life back. They are compassionate and good to the people that come through their doors. It’s a common misconception that pain patients want to take medication. We don’t. We just want some of our lives back and pain medication helps us have that.

A year after my fusion, the surgeon met me again. The fusion had failed, and he wanted to do a revision that would be more painful than the first. He also told me he thought my pain might be caused by fibromyalgia. I’ve never been so angry. I have pain because of my broken neck. Pompous arrogant doctor with no aftercare.

Here is my dilemma, I’ve gotten better care in a big city, where they do not treat me like an addict. I’ve gotten my life back. At first, I was able to go there every three months to get my medication, but with the laws changing, they now say I have to go every month. Driving 6 hours both ways with a 5-year-old and a broken neck is hard. But quality of life and pain are great motivators.

My experience has left me with so much anger towards doctors in my area. It seems their Hippocratic oath has been trumped by the opioid crisis and fear of administrative action. I do not tell people about the medication that helps my quality of life for fear of judgement and stigma. Unless they have been through chronic pain, they simply don’t understand.

I wouldn’t wish this on my worst enemy.

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Bailey Parker lives in Colorado.

Pain News Network invites other readers to share their stories with us. Send them to editor@painnewsnetwork.org.

The information in this column should not be considered as professional medical advice, diagnosis or treatment. It is for informational purposes only and represents the author’s opinions alone. It does not inherently express or reflect the views, opinions and/or positions of Pain News Network.

DEA Adopts Rule to Further Limit Opioid Production

Pat Anson, Editor

The U.S. Justice Department has finalized a new rule that will allow the Drug Enforcement Administration to reduce the amount of opioid pain medication a drug maker can produce if it finds the opioid is being diverted or misused.

The controversial change in the opioid production quota system was adopted despite warnings from patients, doctors and drug makers that it targets the wrong the problem and could worsen shortages of some pain medications.

The DEA maintains the rule change will “encourage vigilance” on the part of opioid manufacturers to prevent their drugs from being abused.

“These common-sense actions directly respond to the national opioid epidemic by allowing DEA to use drug diversion as a basis to evaluate whether a drug’s production should be reduced,” said DEA Acting Administrator Uttam Dhillon in a statement. “This also opens the door for increased communication and better information sharing between DEA and individual states, as we work together to address the opioid problem plaguing our country.”

The final rule greatly enhances the roles played by states and other federal agencies in setting opioid production quotas. It requires DEA to share proposed quotas with state attorneys general, who could object to a quota and demand a hearing.

The rule also allows DEA to consider “relevant information” from all 50 states, the Department of Health and Human Services, Food and Drug Administration, the Centers for Disease Control, and the Centers for Medicare and Medicaid Services, before setting a quota.

"DEA must make sure that we prevent diversion and abuse of prescription opioids. Today's new rule, by taking diversion of these opioids into account, will allow the DEA to be more responsive to the facts on the ground. More importantly, it will help us stop and even prevent diversion from taking place,” said Attorney General Jeff Sessions.

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Sessions announced the proposed rule changes in April, and DEA received over 1,500 public comments during an unusually short comment period. A clear majority opposed the new rule.

“This does nothing to stop addiction or overdose deaths. Addicts will find a high anywhere and where they find it now is street drugs! Illicit drugs are what’s killing, not doctor prescribed opioids filled at a pharmacy. The reporting you all are using is inaccurate and false,” wrote Amy Vallejo.

“By creating quotas, and thereby shortages, you are committing torture,” said Kimberley Comfort, who lives with arachnoiditis, a chronic spinal disease. “There is no reason why people having surgeries, people who suffer from incurable diseases, should be left to suffer when we are a nation that has the ability to take care of its citizens. The DEA does not have a clear understanding of the so-called opioid crisis and therefore needs to cease and desist making opiates harder to get.”

“Again, we have the DEA making laws and quotas on something they should not be. Let them worry about the drugs coming in from China, Mexico etc. which are illegal,” said Sarah Yerxa. “By cutting the quotas all they are doing is sending needy pain patients to the streets, which will just raise the addiction... and overdose problem.”

Opioid Shortages

The DEA has already made substantial cuts in opioid production quotas, reducing them by 25 percent in 2017, followed by another 20 percent cut in 2018. This year’s cuts were ordered despite warnings from drug makers that reduced supplies of opioids “were insufficient to provide for the estimated medical, scientific, research and industrial needs of the United States.”

Many hospitals and hospices now face a chronic shortage of intravenous and injectable opioids, which are used to treat patients recovering from surgery or trauma. The shortage has been primarily blamed on manufacturing problems, although some critics say it has been worsened by the DEA production cuts.

“I believe Attorney General Jeff Sessions needs to sit down and talk to some of these physicians who are pain specialists and understand that what he’s doing is going to put the chronic pain patient, the post-operative patient, and the patient that comes to the emergency room in serious jeopardy,” Tony Mack, CEO and chairman of Virpax Pharmaceuticals, told PNN in an earlier interview.

“I think that Jeff Sessions is not educated well. I think he is picking on something that sounds good politically but doesn’t make sense socially. It’s socially irresponsible.”

In a public notice announcing the rule change, the DEA said it was not responsible for “perceived shortages” of injectable drugs and blamed the “manufacturer induced shortages” on “internal business decisions.”

The agency also deflected criticism that it was targeting the wrong problem. Recent studies indicate that overdoses involving illicit fentanyl, heroin and other street drugs now outnumber deaths linked to prescription opioids.   

“The DEA acknowledges that prescriptions for opioid drug products have decreased over the last several years due to the stepped up civil, criminal, and regulatory enforcement efforts of the agency. However, while there is a downward trend in prescribing, these Schedule II prescription opiates continue to have a high potential for abuse and dependence and require the annual assessment of quotas,” the DEA said.

The agency also claimed prescription opioids were “inextricably linked” to overdoses from heroin and illicit fentanyl, because many addicts start by taking pain medication from family medicine cabinets and then move on to street drugs.

The DEA statement defies some of its own analysis. Less than one percent of legally prescribed opioids are diverted, according to a 2017 DEA report, which also found that admissions for painkiller abuse to publicly funded addiction treatment facilities have declined significantly since 2011, the same year that opioid prescriptions began dropping.

FDA Ends Probe into Kratom Salmonella Link

By Pat Anson, Editor

The Food and Drug Administration has ended its investigation of a small salmonella outbreak linked to kratom – but not without taking some parting shots at the herbal supplement used by millions of Americans to treat chronic pain, addiction, depression and other conditions.

“It appears the salmonella problem with kratom uncovered earlier this year has probably been occurring for some time and is ongoing. We have closed our outbreak investigation, concluding that anyone consuming kratom may be placing themselves at a significant risk of being exposed to salmonella,” said FDA commissioner Scott Gottlieb, MD, and Stephen Ostroff, MD, FDA Deputy Commissioner for Foods and Veterinary Medicine, in a lengthy joint statement.

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The FDA ended its investigation five weeks after the Centers for Disease Control and Prevention wrapped up its own probe of the salmonella outbreak that sickened 199 people in 41 states. The CDC investigation began in February of this year, but salmonella illnesses linked to kratom were traced back as far as January 2017.

No single source of the outbreak was ever identified, but kratom was considered the “likely source.” A little over half of the 81 kratom samples that were analyzed tested positive for strains of salmonella bacteria.

“This means that users of these products had essentially a one in two chance of being exposed to this pathogen,” Gottlieb and Ostroff said. “The more than 50 percent contamination rate is stunningly high. It represents a level rarely seen in outbreak investigations of this nature. It shows that a high proportion of kratom being shipped into the United States may be contaminated with salmonella.”

Kratom comes from the leaves of a tree that grows in southeast Asia, where it has been used for centuries as a natural pain reliever and stimulant, particularly in rural areas of Indonesia and Thailand.  

“In these locations, the plant is being grown, harvested and processed in problematic conditions that readily create the circumstance for widespread contamination with foodborne pathogens. Although some of the kratom is further processed once in the United States into capsules, powders or herbal remedies, based on our findings, these procedures do not appear to be eliminating microbial contamination,” wrote Gottlieb and Ostroff.

In recent years, millions of Americans have discovered kratom and started buying it online or in convenience stores and “head shops.” But not until this year did federal health officials show any concern that kratom products were contaminated with salmonella bacteria. Their primary focus was that kratom was being marketed as an unapproved medical treatment, particularly for pain and addiction.

The FDA has even started calling kratom an addictive “opioid,” when in reality its active ingredients are mitragynine and 7-hydroxymitragynine, two alkaloids that are believed to act on opioid receptors in the brain. Earlier this year, the FDA released a computer analysis that found kratom contains over two dozen opioid-like substances – a report that critics say was biased and amounted to “junk science.”

Over a dozen kratom products were recalled during the FDA and CDC salmonella investigations. Salmonella is a bacterial infection usually spread through contaminated food or water. Most people who become infected develop diarrhea, fever and stomach cramps. Severe cases can result in death.

There have been several other salmonella outbreaks this year, including infections linked to melons, raw sprouts, dried and shredded coconut, live poultry, chicken salad, pet guinea pigs, and Kellogg’s Honey Smacks cereal.