CDC Warning: Kava Poisoning Calls Have Climbed Sharply — Here's What the Data Actually Says

Kava (Piper methysticum) is a plant from the Pacific Islands. For thousands of years, Pacific communities have ground its roots and steeped them in cold water to make a calming ceremonial drink. The active compounds, called kavalactones, reduce anxiety and produce a mild euphoria. Traditional root-only preparations have a long record of apparently safe use.

Over the last decade, kava has moved into Western supplement culture as an anxiety remedy and an alcohol alternative. Kava bars have opened across the United States, and capsules and concentrated extracts are sold in wellness shops and online. The problem: the Western supplement market has industrialized and concentrated a substance whose safety depends heavily on how it is prepared. In April 2026, the CDC published a detailed look at what has happened since — and the numbers are striking.

What the 2026 CDC Report Actually Says

On April 3, 2026, the CDC's Morbidity and Mortality Weekly Report (MMWR) published an analysis of kava-related calls to America's Poison Centers from January 2000 through June 2025 (Towers et al., MMWR 75(12);2026). The authors reviewed 1,955 kava exposure calls across 25+ years. The headline finding: the share of calls rated as a "serious medical outcome" rose from about 12% in 2000 to a peak of 39% in 2024, then 32% in the first half of 2025. A "serious medical outcome" means the person needed medical treatment or had notable clinical effects — not that they died.

Call volume itself has climbed sharply in recent years, likely because kava bars and concentrated extracts have grown popular. A second pattern in the data: many of the worst calls involved co-use with kratom. In the first half of 2025, roughly 30% of kava calls also involved kratom, up from near zero in earlier years. Kratom has its own hepatotoxicity signal, and the combination appears to drive a disproportionate share of serious outcomes.

Importantly, the MMWR dataset did not identify any cases of acute liver failure from kava alone. Elevated liver enzymes — an early warning sign of liver stress — appeared in about 1.7% of kava-only calls and about 6.3% of kava-plus-kratom calls. That is higher than expected for a "natural" product, but it is different from the transplant-level liver failure cases that made headlines in Europe 20 years ago. Those European cases are real and are discussed below, but they came from a different pattern of use (concentrated extracts, often with other drugs or alcohol) and they are not what the 2026 CDC data describe.

The CDC authors recommended that healthcare providers ask patients directly about kava and kratom use when evaluating unexplained liver enzyme elevations, because patients often do not volunteer supplement use.

Traditional Kava vs. Concentrated Supplement Extracts

Western consumers are often unaware of a key distinction. Traditional kava uses only the root, prepared as a cold-water extraction. The kavalactone dose is modest and fairly consistent, and the process leaves behind certain plant compounds found in the stem, leaves, and peelings that are linked to liver toxicity.

Most Western commercial kava products — capsules, concentrated extracts, and powders marketed as "full-spectrum" — are made differently. Early investigations into kava-associated liver injury in Germany and Switzerland in the early 2000s (which led to temporary bans in several European countries) found that many implicated products mixed "noble" and "tudei" kava varieties, used above-ground plant parts, and concentrated kavalactones well above the levels delivered by traditional drinks.

Flavokavain B, a chalcone compound present in kava leaves and stem bark but at very low levels in root preparations, has been identified in lab and animal studies as a likely contributor to liver toxicity. It can trigger programmed cell death in liver cells at concentrations reachable with concentrated extracts. Traditional root-only preparations contain very little flavokavain B; whole-plant or above-ground-part extracts contain substantially more.

The result: people buying kava supplements online cannot usually tell whether a product uses root-only noble kava at traditional strength, or a concentrated whole-plant extract that may carry a very different risk. Most labels do not disclose this clearly.

Who Is Most at Risk

Certain groups face sharply higher risk from kava and should avoid it:

• People with pre-existing liver disease (hepatitis B or C, fatty liver disease, cirrhosis)
• Anyone taking drugs that can stress the liver, including high-dose acetaminophen (Tylenol), statins, isoniazid (a TB drug), or methotrexate
• People who drink alcohol regularly — the combination amplifies liver stress
• Anyone on drugs processed by the CYP450 liver enzyme system, because kava blocks several of these enzymes and can change how dozens of medications are cleared
• Anyone using kratom — based on the CDC's 2026 data, this combination shows the worst outcomes
• Pregnant or breastfeeding women

Genetic variation in CYP2D6, a liver enzyme involved in kavalactone metabolism, may help explain why some people develop liver injury at doses others tolerate. That individual variability makes population-level risk hard to predict.

Regulatory History and Current Status

Germany, France, Switzerland, and Canada issued bans or strong warnings on kava products in the early 2000s following reports of liver failure. Germany lifted its ban in 2014 after its Federal Institute for Risk Assessment (BfR) concluded that the risk was tied mainly to non-traditional extracts, and that water-based root extracts had a different risk profile. The UK Medicines and Healthcare products Regulatory Agency (MHRA) still maintains restrictive guidance.

The U.S. FDA issued a consumer advisory in 2002 noting rare but severe liver injury. The agency has not banned kava but continues to monitor adverse events through its MedWatch system. The 2026 CDC MMWR escalates official concern given the growth of kava bars, concentrated extracts, and kratom co-use.

What to Do If You Use Kava

If you use kava supplements or go to kava bars, the most important steps are: avoid daily use, avoid combining with alcohol, kratom, or sedative medications without medical guidance, and watch for early signs of liver stress — unusual fatigue, nausea, yellowing of skin or eyes (jaundice), dark urine, or pain in the right upper abdomen. If any of those show up, stop use and see a doctor. If you use kava regularly, ask your doctor about checking liver enzymes (AST, ALT, bilirubin).

Kava's anxiety-reducing effect is real and the plant carries a cultural legitimacy that deserves respect. But the Western supplement market has concentrated and industrialized a substance whose safety depends on preparation method, dose, and what else you are taking — and it has done so without enough warning to the consumer.