Ong Tien USA LLC Receives FDA Warning Letter After Lab Testing Confirms Hidden Pharmaceutical Ingredients

FDA's active market surveillance program has produced another enforcement action with direct implications for product integrity monitoring: Ong Tien USA LLC, a Houston-based online seller, received a warning letter dated October 26, 2026, after agency laboratory analysis confirmed that a product marketed as a dietary supplement contained undisclosed piroxicam and dexamethasone phosphate.

The agency purchased the product directly from the company's website, ongtienlinhchi.com, as part of a review initiated in April 2026. Notably, the product received differed from the one ordered, a substitution that itself triggered a misbranding citation under section 502(a) of the FD&C Act, 21 U.S.C. 352(a). Three products in total were cited as unapproved new drugs under section 505(a), meaning none held the required FDA approval for interstate commerce.

The confirmed presence of piroxicam, an NSAID carrying cardiovascular and gastrointestinal risk warnings, and dexamethasone phosphate, a corticosteroid with immunosuppressive and metabolic effects, in an unlabeled context represents a serious sterility and safety assurance failure. Neither ingredient appeared on product labeling, leaving consumers and healthcare providers without the information required to assess contraindications or drug interactions.

For regulatory affairs leads tracking enforcement trends, the mechanism here is significant: FDA did not rely on a facility inspection or a consumer complaint to initiate action. The agency purchased the product through normal commercial channels, subjected it to laboratory analysis, and built the violation record from that evidence base. That approach is consistent with CDER's stated public health mandate and signals continued investment in e-commerce surveillance as a compliance vector.

The warning letter explicitly reserves the right to pursue seizure and injunction without further notice if violations are not promptly corrected, a standard escalation posture that nonetheless underscores the agency's willingness to move to judicial remedies against online distributors operating outside 21 CFR Part 211 and FD&C Act requirements.

The adequacy of Ong Tien USA LLC's corrective response, and whether CDER proceeds to further enforcement, will serve as a measurable indicator of how the agency calibrates follow-through on web-based distribution violations in the current inspection cycle.

Source: FDA Center for Drug Evaluation and Research (CDER) via FDA.gov Warning Letters database, October 26, 2026; published November 3, 2026.