The Rise of Herbal Supplements and Their Hidden Risks

Tiny blue bottles line the aisles of tens of thousands of convenience stores, smoke shops, and other retailers across the country. Botanic Tonics’ Feel Free tonic is labeled as a “plant-based herbal supplement” and promises to boost energy, mood, and focus. Tonics like this have been increasingly marketed as an alternative to substances like alcohol. However, a growing body of evidence suggests that the substances making up the basis of products like Feel Free pose several health risks, including liver damage, especially when overconsumed.

Kava and kratom, two herbal substances found in Feel Free tonics and other herbal supplements, have risen in popularity in the United States over the past few years. Kava is often promoted as a supplement that could help with anxiety due to the plant’s sedative effect. Beverages containing kava are marketed as alcohol alternatives, leading to the opening of kava-focused bars across the country.

Kratom also has a sedative effect in large amounts, though it is stimulating in smaller doses. Larger doses of kratom cause pain relief and euphoria through opiate-like effects, leading many people to self-medicate with kratom as a way to combat opioid withdrawal symptoms. Others take it to experience its mood-enhancing effects and feel more energetic. The addiction risk from kratom is higher than the risk posed by kava.

The nutrition information on Feel Free tonics states that one serving of their “classic” tonic is half of the two-ounce bottle, and that consuming more than one serving at a time is not advised. However, many people sharing their stories of addiction to tonics like these say they would drink an entire two-ounce bottle at a time and progressed to drinking multiple bottles a day. 

In the CDC’s Morbidity and Mortality Weekly Report, Eleanor Towers and colleagues examined the frequency of kava- and kratom-related reports to 53 poison centers across the country.

They found that calls to poison centers about complications from kava consumption have increased by 383% from 2011 to 2025, and kratom toxicity calls have skyrocketed over 1,200% within the last decade. Many people who were hospitalized for kava toxicity ingested the substance alongside kratom, usually through products that combine the two, like Feel Free. Common symptoms of toxicity from either or both substances included nausea and vomiting, drowsiness, and an abnormally fast heart rate. Six percent of reports of kava and kratom toxicity showed signs of enzymes in the bloodstream that indicate cellular and liver damage. Cases of liver injury have been linked to habitual kava consumption.

Men aged 20-39 accounted for most of the poisoning reports, but older adults aged 40-59 have increasingly made up a large portion of the calls. Hospitalizations from kratom exposure also saw a similar astronomical rise, increasing from 43 in 2015 to 538 in 2025.

Currently, the FDA has taken steps to regulate a specific potent chemical compound found in kratom, but not products containing the whole leaf, such as Feel Free. Recent reporting from The New York Times found links between prominent personnel in the kratom industry and the Trump administration, suggesting that the government shifted its focus away from natural kratom regulations to protect personal interests.

Although kava and kratom are not classified as controlled substances, the latter is considered a “drug and chemical of concern,” and neither is approved by the FDA as a food additive or supplement. Six states have banned kratom, but kratom-containing products remain available for purchase at vape stores, gas stations, and convenience stores across the country. Many states have adopted legislation promoted by the American Kratom Association to urge restrictions on the substance instead of outright bans. The possession of kava is legal across the country, but recent regulations at the state and city levels have tightened restrictions on whether it can be included in restaurant food. Recent restrictions in New York City have led to the closure of some kava bars. 

As a result of recent lawsuits, Botanic Tonics has updated the packaging on its kratom-containing products to note that the substance can be habit-forming, like nicotine or alcohol. Still, the authors of the CDC report urge more surveillance of a wider array of kratom and kava products to get a better understanding of the various risks of these popular substances. As many of these products are promoted with terms like “natural” and “plant-based,” consumers may not grasp their true potency until it is too late.