OPMS Kratom: What the FDA Warning Means

FDA tells people not to use OPMS Black Liquid Kratom. On July 26, 2024 the agency said the product has been linked to serious adverse health effects, including death. The page below covers what FDA reported, what we know about liquid kratom, and what to do if you already use it.

What did the FDA say about OPMS Black Liquid Kratom?

OPMS stands for Optimized Plant Mediated Solutions. The FDA’s consumer warning says the product is a liquid sold online and in some stores. The label lists the kratom alkaloids mitragynine and 7-hydroxymitragynine (7-OH).

The warning followed a report of a person who died after using the product. FDA also listed other reports:

• Withdrawal symptoms and addiction
• Digestive problems
• Restless leg syndrome
• Skin problems
• Aggressive behavior
• Increased anxiety
• Low energy and trouble concentrating

FDA says plainly: “Consumers should not consume OPMS Black Liquid Kratom.” The page says the agency is investigating the complaints. It gives no alkaloid amounts for the product.

Is kratom legal to sell as a supplement or drug?

No. FDA says there are no prescription or over-the-counter drug products containing kratom. It says kratom is not appropriate as a dietary supplement and is an unsafe food additive when added to food (FDA kratom page).

Some states and cities ban or restrict kratom, and rules change. Check your local law.

Is liquid kratom stronger than leaf?

FDA says 7-OH is far more potent at the mu-opioid receptor than mitragynine and classic opioids like morphine. In natural leaf it makes up less than 2% of the alkaloids. A product label that lists 7-OH tells you the dose of that alkaloid can be much higher than in leaf.

One survey of 421 kratom users found liquids were linked to taking more than intended. Edibles were linked to tolerance (Hill et al., 2025).

Can kratom treat opioid addiction?

Kratom is not an approved treatment for opioid addiction. FDA lists substance use disorder among its kratom safety concerns. If you depend on opioids, talk to a doctor about approved medicines.

A survey of 2,061 kratom users found 25.5% met criteria for kratom use disorder. Tolerance and withdrawal were the most common symptoms (Hill et al., 2024).

Do OPMS strains like Gold, Silver or Malay work differently?

Nobody has shown it. A survey of 644 kratom users found people described different effects for red, green and white products. A lab analysis of the products showed no significant difference in alkaloid content between colors. The authors say marketing and expectation may shape what people report (Huisman et al., 2023). Strain names on a bottle don’t tell you the dose.

What are the other risks?

• FDA lists liver toxicity, seizures and substance use disorder.
• FDA says deaths linked to kratom usually involved other drugs, so kratom’s role is unclear.
• FDA has also warned about products contaminated with Salmonella or concerning levels of heavy metals.
• A small trial of 12 healthy adults found kratom tea raised blood levels of midazolam, a drug cleared by the CYP3A enzyme. The authors say combining kratom with drugs cleared this way could cause serious interactions (Tanna et al., 2023).
• FDA is aware of newborns with withdrawal signs after prolonged exposure to kratom before birth.

What should you do if you already use it?

Talk to a healthcare provider if you have bad symptoms or want to cut back. Don’t stop prescribed medicines on your own. If you take any medicine, ask a pharmacist about kratom first. You can report a serious reaction through FDA’s consumer complaint page.

Looking for products with lab testing? See our guide to kratom vendors. For how kratom compares for pain, see our kratom for pain guide.

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