Undeclared Clobetasol Found in 6 of 18 Selected OTC Skin Products
Key Takeaways
- Undeclared active ingredients were found among deliberately selected online OTC skin products marketed for persistent skin complaints or hyperpigmentation.
- Clobetasol appeared in every positive product, and its highest measured concentration exceeded the cited approved topical strength.
- Two positive products also contained unlisted miconazole or terbinafine.
- Undeclared active ingredients recurred in additionally purchased units of the positive products.
Abilov and colleagues conducted a targeted quality-improvement laboratory assessment of online over-the-counter (OTC) skin products, as described in a JAMA Network Open research letter. Selection criteria were efficacy claims for inflammatory or persistent skin conditions, including dermatitis, psoriasis, eczema, or hyperpigmentation; no listed clinically proven ingredients for those conditions; and at least 100 reviews on one online platform. Products with prior reports of undeclared ingredients, or with branding or labeling similar to previously identified products, were also eligible if they met at least one of these criteria.
Investigators screened for 28 corticosteroids and antifungals using high-resolution liquid chromatography–mass spectrometry, with tandem mass spectrometry confirmation. They purchased products from February through December 2025 and analyzed them from April 2025 through April 2026. After an initial positive finding, they purchased and tested two additional units of the same product. No patients were studied.
Among 18 deliberately selected products, six (33.3%) contained an undeclared active ingredient. Clobetasol propionate was present in every positive product; miconazole and terbinafine were the additional unlisted antifungals identified. All three analyzed units of each positive product contained an undeclared active ingredient. According to the investigators, the positive products also attracted substantial combined online review activity.
Measured clobetasol concentrations ranged from approximately 0.01% to 0.46%. At the upper end, the concentration was 9.2 times the cited 0.05% strength of Food and Drug Administration (FDA)-approved topical formulations. This comparison concerns concentration in a tested product, not a measured dose received by a user.
Deliberate selection and the small sample mean the observed yield cannot be interpreted as prevalence across the US OTC skin-product market. Other chemical forms could also have escaped the assay. With no patients in the assessment, Abilov and colleagues measured neither population exposure nor adverse events or treatment efficacy. The authors identified skin atrophy, steroid acne, dyspigmentation, and hypothalamic-pituitary-adrenal axis suppression as potential consequences of chronic clobetasol exposure, not harms observed among users of these products.
Abilov and colleagues found unlisted prescription-only clobetasol in targeted testing of online skin products and suggested that targeted detection could inform surveillance.
Clinician Questions
Did users of online OTC skin products containing clobetasol develop glaucoma?
No glaucoma outcomes were measured among users of the tested products. Abilov and colleagues cited an association from prior literature between periocular clobetasol exposure and glaucoma as a potential concern, but did not establish that anyone applied the products near the eyes.
Could undeclared clobetasol explain apparent improvement with online OTC eczema or psoriasis products?
Abilov and colleagues suggested that undeclared pharmacologically active ingredients might account for apparent efficacy of products marketed for eczema or psoriasis. Their assessment measured product ingredients, not patient treatment responses, and established neither clinical efficacy nor actual product use.