Ask the Doctors

Dear Doctor: What, exactly, is kratom? The FDA has apparently called it an opioid, even though it seems to be an herbal supplement. Is it safer than prescription opioids? I'm afraid of opioids, but if this is safer, I'll try it.

Dear Reader: Before we start, let's reflect just a moment on the opioid epidemic in America. The origin of this epidemic stems from the medical community's desire to control pain: Pain was the enemy and opiates were the cure. But over the years, the addictive potential of these drugs has destroyed multiple lives. As a society, we're now using other medications to control pain, while actively searching for more.

Some consider kratom (Mitragyna speciosa), a tree native to southeast Asia, to have potential in this respect. Kratom has been used in traditional medicine since the 1800s, with the leaves of the tree chewed or made into a tea. These leaves contain many compounds, but two specifically -- mitragynine and 7-hydroxymitragynine -- appear to have the primary pain-relieving effects. These compounds attach to and stimulate the mu-opioid receptor in the brain, creating positive reinforcement, while blocking the pain-relieving effect on two other opioid receptors. Kratom also contains chemicals that attach to other brain receptors, possibly encouraging calm. Further, because kratom is part of the caffeine family, the tree's leaves also appear to have stimulating effects.

People who have used kratom have reported pain relief, relaxation, improved mood and decreased anxiety. Because of its pain-relieving mechanism and because it works via the opiate receptors, kratom has been considered a potential alternative to traditional opiates, with perhaps even the ability to help wean people off opiates.

We already have some history with the substance, because kratom has been available in the United States since 2010. One study, from 2017, surveyed 500 men and women in recovery centers about their use of kratom. About 21 percent had used kratom once, and 10 percent had used it in the past year. Kratom users were more likely to be college-educated and younger than addicts who had never used kratom. In fact, many had used kratom to deal with their opiate addiction.

Although these findings could suggest that kratom may hold promise against pain and opiate addiction, we simply don't have good studies of its effectiveness.

And it may have serious side effects. The substance is cleared from the body through the liver, so if a person has liver problems or is taking medications metabolized by the liver, it may stay in the bloodstream. From 2010 through 2015, 660 calls were made to poison control regarding kratom; 65 percent of these callers had used kratom by itself, without additional substances. Callers complained of rapid pulse rates, agitation, drowsiness, nausea and elevated blood pressure.

Symptoms can be amplified to life-threatening levels when kratom is mixed with alcohol and prescription or illicit drugs, sometimes leading to liver toxicity, seizures and death. Kratom was linked to 15 deaths between the years 2014 and 2016; of note, these deaths do not appear related to use of kratom with other drugs -- just kratom alone. That said, the number of deaths from prescribed opiate medications far outnumber the deaths thus far from kratom.

In summary, although the potential for abuse of kratom appears less than that for more traditional opioids, the fact remains that kratom does work on the mu-opioid receptor, meaning it can be abused. That potential prompted the FDA to recently warn of kratom's opioidlike properties and potential for risk.

In short, we need more studies of kratom -- and better replacements for opioids. As of now, I would look for other ways to manage pain.

(Send your questions to askthedoctors@mednet.ucla.edu, or write: Ask the Doctors, c/o Media Relations, UCLA Health, 924 Westwood Blvd., Suite 350, Los Angeles, CA, 90095. Owing to the volume of mail, personal replies cannot be provided.)

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