Some of these products contain active ingredients found in anti-inflammatory prescription medication.
“These products may cause potentially serious side effects and may interact with medications or dietary supplements a consumer is taking,” the FDA said in a statement. “It is clear from the results of our decade of testing that retailers and distributors, including online marketplaces, do not effectively prevent these types of potentially harmful products from being sold to consumers.”
Unlike prescription medication and over-the-counter drugs such as loratadine (Claritin) or acetaminophen (Tylenol), supplements do not need FDA approval before they can be sold. Only after a complaint is made or FDA testing reveals illegal or unsafe ingredients can the FDA get involved.
From August 2013 to September 2023, the FDA identified 22 arthritis and pain products with active ingredients not disclosed on the product label. The most common hidden ingredients detected in these supplements were prescription-only corticosteroids, nonsteroidal anti-inflammatory drugs (NSAIDs), and muscle relaxants, said Candy Tsourounis, PharmD, a professor in the department of clinical pharmacy at the University of California, San Francisco.
Kuka Flex Forte and Reumo Flex, both promoted for joint pain and arthritis, both contain the NSAID diclofenac. Tapee Tea, a product promoted for pain relief, contains dexamethasone and piroxicam. AK Forte, also sold for joint pain and arthritis, contains diclofenac, dexamethasone, and methocarbamol not disclosed on the label.
“It is interesting that these products have hidden ingredients that are used to reduce swelling and inflammation,” Dr. Tsourounis said. “I don’t know if this was intentional, but it seems suspicious that a product marketed to reduce joint pain and inflammation contains prescription-only ingredients that are used for this purpose.”
Certain products also contained antihistamines including cyproheptadine and chlorpheniramine.
These types of products are likely targeted toward underserved and immigrant communities, added Pieter Cohen, MD, a primary care physician and an assistant professor of medicine at Harvard Medical School, Boston, who studies dietary supplements. They might be sold in mom-and-pop shops or gas stations to individuals with limited access to health care or insurance, he noted.
The FDA warned that this list included “only a small fraction of the potentially dangerous products marketed to consumers online and in stores. Even if a product is not included in this list, consumers should exercise caution before using these types of arthritis and pain management products.”
Advising patients
Research suggests that most patients do not tell doctors about the supplements they are taking, and often, clinicians do not ask, said Dr. Cohen. “Most of the time it’s a total black box – we don’t know what’s going on,” he added.
He advised raising the subject of supplements in a very nonjudgmental way, particularly when treating patients in marginalized and immigrant communities. One approach he suggested was first mentioning that other patients in your care dealing with joint pain have bought remedies locally or have tried treatments that friends recommend. You can then ask a patient about their own use, framing it as a way to better help with treatment decisions.
Once a clinician understands what their patient is taking, they can then give advice and discuss if a product is safe to combine with prescription drugs, Dr. Cohen said. “If they come down too hard, I think the patients will just clam up and not talk about it anymore,” he said.
If a patient begins to experience side effects or gets sick, a clinician will already be informed of what their patient is taking and can ask that patient to bring the product or supplement in, so they can look over the product together, Dr. Cohen noted. Any side effects or other adverse events potentially related to the use of these products should then be reported to FDA’s MedWatch Safety Information and Adverse Event Reporting Program.