[10-6-2025] The Food and Drug Administration is advising consumers not to purchase or use Osteo Sin Max, a product promoted and sold for joint pain on various websites, including ebay.com, and possibly in some retail stores.

FDA laboratory analysis confirmed that Osteo Sin Max contains dexamethasone, methocarbamol and phenylbutazone not listed on the product label.

Dexamethasone is a corticosteroid commonly used to treat inflammatory conditions. Corticosteroid use can impair a person’s ability to fight infections and can cause high blood sugar levels, muscle injuries and psychiatric problems. When corticosteroids are taken for a prolonged period or at high doses, they can suppress the adrenal gland. Abrupt discontinuation can cause withdrawal symptoms. Additionally, the undeclared dexamethasone in Osteo Sin Max may cause serious side effects when combined with other medications.

Consumers taking Osteo Sin Max should immediately consult with their health care professional to safely discontinue use of this product. The risks of withdrawal from corticosteroids should be assessed by a health care professional. Only licensed health care professionals can evaluate patients for the risk or existence of adrenal suppression.

Methocarbamol is a muscle relaxant that can cause sedation, dizziness and low blood pressure. Methocarbamol also can impair mental and physical abilities to perform certain tasks, such as driving a motor vehicle or operating machinery.

Phenylbutazone is a non-steroidal anti-inflammatory drug (NSAID) that was discontinued for human use in the U.S. due to the risk of serious and life-threatening injuries. The most serious and life-threatening injury associated with phenylbutazone treatment is bone marrow toxicity, which occurs when the body does not produce enough red blood cells, white blood cells and/or platelets. Certain types of bone marrow toxicity are reversible; however, in rare circumstances it can lead to death. Patients with anemia, low white or red blood cell count or decreased blood platelets may be at a greater risk of death or serious injury.

Health care professionals and consumers should report adverse events or side effects related to the use of this product to FDA’s MedWatch Safety Information and Adverse Event Reporting Program:

This notification is to inform the public of products potentially marketed as dietary supplements or conventional foods with hidden drug ingredients and chemicals. These products are typically promoted for sexual enhancement, weight loss, pain relief and body building and are often represented as being all natural. Consumers should exercise caution before purchasing these products.

FDA is unable to test and identify all products marketed as dietary supplements that have potentially harmful hidden ingredients.

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