7-OH and liver toxicity: what the research actually shows

At a glance: the state of the evidence

Key Takeaways

• Kratom is a documented cause of drug-induced liver injury. The DILIN prospective study enrolled 11 kratom-associated liver injury cases between 2004 and 2019, with 8 of those cases occurring in the final 6 years, reflecting rapid growth in kratom use.
• A 2023 Journal of Hepatology case study noted that alternative and herbal supplements are now the second most common cause of DILI in the U.S., with kratom implicated in cholestatic and mixed-pattern liver injury.
• A 2025 peer-reviewed review (Alsbrook, Pro, and Koturbash, Pharmaceutical Biology) concluded that kratom's hepatotoxicity signals are heterogeneous, idiosyncratic, and frequently confounded by product heterogeneity and co-exposures rather than predictable dose-dependent hepatic toxicity.
• The same 2025 review found that 7-OH's toxicological profile is dominated by opioid-class effects. Its best-documented danger is respiratory depression, dependence, and overdose, not liver injury.
• Unregulated products, unknown contaminants, and co-use with alcohol or kava make it difficult to isolate what is causing liver injury in any individual case.

What the kratom-DILI evidence shows

Drug-induced liver injury from herbal and dietary supplements has increased significantly in the United States over the past two decades. A 2023 Journal of Hepatology case study by Roma et al. noted that alternative medicine supplements are now the second most common cause of DILI in the U.S. Kratom has been implicated in multiple published case reports and case series, and in the DILIN prospective registry, which is the most rigorous U.S. database for tracking drug-induced liver injury.

Between 2004 and 2019, the DILIN enrolled 11 cases of kratom-associated liver injury. The pattern in that data was notable: only 3 cases were enrolled in the first ten years of the registry (2004 to 2013), with 8 enrolled in the following six years, directly tracking the rapid increase in U.S. kratom use during that period. The typical presentation was a healthy patient, most often male, presenting with jaundice and itching, a mixed or cholestatic pattern of liver injury, and a median time from kratom use to onset of symptoms of approximately 22 days.

Cholestatic injury means the liver's bile flow is disrupted. It typically appears on blood tests as elevated bilirubin and alkaline phosphatase (ALP), sometimes alongside elevated ALT and AST. The 2023 Journal of Hepatology case documented a 47-year-old male who presented with jaundice and significant unintentional weight loss after kratom use, consistent with this pattern.

Most kratom-associated liver injury cases in the published literature recovered with supportive care after stopping the substance. Acute liver failure from kratom has been documented but is rare.

Why 7-OH liver toxicity is harder to establish

The documented kratom-DILI cases were not caused by concentrated 7-OH products specifically. Most DILIN cases and published case reports describe traditional kratom use (leaf powder, capsules, or tea), not the concentrated 7-OH tablets that have emerged in the U.S. market in recent years. Whether concentrated 7-OH products produce more, less, or different liver injury than botanical kratom is not yet well characterized by dedicated clinical data.

The 2025 review by Alsbrook, Pro, and Koturbash in Pharmaceutical Biology addresses this directly. It concluded that kratom's hepatotoxicity signals across the literature are heterogeneous, often idiosyncratic, and frequently confounded by multi-ingredient products or co-exposures. This places kratom in the same category as other herbal dietary supplements that show sporadic drug-induced liver injury rather than predictable dose-dependent hepatic toxicity. The review then drew a clear contrast with 7-OH's consistent, classical opioid-type pharmacodynamic signal: respiratory depression, tolerance, dependence, and withdrawal when exposure is sufficient.

Kratom is a documented cause of drug-induced liver injury, but a distinct, dose-dependent liver toxicity from 7-OH specifically has not been well established. Its clearest danger is opioid toxicity.

Why 7-OH's liver risk is hard to pin down

Several factors make it difficult to draw clean conclusions from the available liver injury data, even in cases attributed to kratom or 7-OH products:

Product heterogeneity is particularly significant. A peer-reviewed analysis of commercial concentrated 7-OH products found that labeled potency did not reliably match actual 7-OH concentration, with one brand showing different values on its front and back labels, neither matching the measured concentration. Consumers cannot use product labels to assess what their liver is actually being exposed to.

Warning signs of liver trouble and when to get help

Liver injury is often silent in its early stages. The signs that should prompt a clinical evaluation include:

• Yellowing of the skin or whites of the eyes (jaundice)
• Dark urine (tea-colored or brown)
• Pale or clay-colored stools
• Persistent nausea or loss of appetite
• Fatigue out of proportion to activity level
• Itching without an apparent rash
• Pain or discomfort in the upper-right abdomen

If you have any of these symptoms and have been using kratom or concentrated 7-OH products, stop use and see a clinician promptly. Ask for liver function testing: ALT, AST, alkaline phosphatase, and bilirubin. Most kratom-related liver injury improves once the substance is stopped, with supportive care. Early attention matters because progressive liver injury is easier to manage before it has advanced.

The bigger, better-documented danger

Even where the liver question remains unsettled, 7-OH's opioid risks are not uncertain. The FDA's 2025 scientific assessment documented respiratory depression, physical dependence, and withdrawal consistent with classical opioids, and described 7-OH as a "novel potent opioid" and an emerging public health threat. The DEA filed notices of intent for temporary Schedule I placement in July 2026. County medical examiners have documented fatal overdoses tied to concentrated 7-OH products.

For people who have developed dependence on 7-OH, buprenorphine/naloxone (Suboxone) is FDA-approved to treat opioid use disorder and is effective for 7-OH dependence because it stabilizes the same mu-opioid receptors that 7-OH acts on. It is available through a telehealth visit in most states, often on the same day someone reaches out. Learn how Bicycle Health's treatment works.

Frequently Asked Questions

Does 7-OH damage your liver?

Kratom as a botanical has been linked to drug-induced liver injury in published case reports and the DILIN prospective registry. Whether concentrated 7-OH specifically causes liver damage in a direct or dose-dependent way is not yet well established. A 2025 review in Pharmaceutical Biology concluded that kratom's hepatotoxicity signals are heterogeneous and idiosyncratic, and that 7-OH's clearest documented risk profile is opioid-type toxicity, not hepatic. This is not reassurance. It is an accurate summary of what the current evidence does and does not show.

What does kratom liver injury look like on a blood test?

The most common pattern in documented cases is cholestatic: elevated bilirubin and alkaline phosphatase, sometimes accompanied by elevated ALT and AST. Onset typically occurs within a few weeks of frequent use. If you have these findings and have been using kratom or concentrated 7-OH products, tell your clinician so they can factor it into the evaluation.

Can you recover from kratom-related liver injury?

Most documented cases of kratom-associated DILI have recovered with supportive care after the substance was stopped. Acute liver failure is rare but has been documented. Earlier identification and discontinuation of the substance is associated with better outcomes.

Is it safe to use 7-OH if my liver enzymes are currently normal?

Normal liver enzymes at one time point do not mean 7-OH is safe. The opioid risks of concentrated 7-OH, including respiratory depression, physical dependence, and overdose, are independent of liver function and are the most consistently documented dangers. Normal labs do not predict what happens with continued use, and the risk of a fatal overdose does not depend on liver status.

What should I do if I am concerned about liver damage from kratom or 7-OH?

Stop use and see a clinician. Ask for liver function testing including ALT, AST, ALP, and bilirubin. Be honest with your provider about what you have been using and for how long. If dependence makes it difficult to stop, buprenorphine-based treatment is available and effective for 7-OH dependence. See how Bicycle Health's treatment works.

How long after stopping kratom does liver injury improve?

The clinical literature does not establish a fixed recovery timeline, but most documented kratom-DILI cases showed improvement after stopping the substance with supportive care. How quickly liver function tests normalize depends on the severity of injury, the individual's overall health, and whether any other contributing substances are also stopped. A clinician can monitor your labs and advise based on your specific results.