Hidden Drugs Found in 3 Supplements Promoted for Joint Pain, Arthritis

The Food and Drug Administration (FDA) is advising against the purchase of several dietary supplements that are being promoted for the treatment of joint pain and rheumatoid arthritis as these products contain hidden drug ingredients.

Specifically, the Agency has issued alerts for Fast-Act Rheuma Capsule, New Fast-Act Rheumatism Capsule, and UA-Block. These dietary supplements were sold online on various websites as well as in retail stores.

Laboratory analysis has confirmed the following active ingredients have been identified in these products and are not listed on the label:

  • Fast-Act Rheuma Capsule: Prednisone-21-acetate, a corticosteroid, and piroxicam, a nonsteroidal anti-inflammatory drug (NSAID);
  • New Fast-Act Rheumatism Capsule: Indomethacin, an NSAID;
  • UA-Block: Indomethacin.

Individuals taking these supplements may be at increased risk for serious side effects (eg, cardiovascular events, gastrointestinal damage), especially if they are already using a medication that contains an NSAID, or are on a medication that interacts with the hidden ingredient. Additionally, the use of corticosteroids for a prolonged period of time can lead to adrenal suppression, with abrupt cessation resulting in withdrawal symptoms.

Adverse events related to these products should be reported to the FDA’s MedWatch program.

This article originally appeared on MPR


  1. Food and Drug Administration. Fast-Act Rheuma Capsule contains hidden drug ingredients. May 8, 2023. https://www.fda.gov/drugs/medication-health-fraud/fast-act-rheuma-capsule-contains-hidden-drug-ingredients.
  2. Food and Drug Administration. New Fast-Act Rheumatism Capsule contains hidden drug ingredient. May 8, 2023. https://www.fda.gov/drugs/medication-health-fraud/new-fast-act-rheumatism-capsule-contains-hidden-drug-ingredient.
  3. Food and Drug Administration. UA-Block contains hidden drug ingredient. May 8, 2023. https://www.fda.gov/drugs/medication-health-fraud/ua-block-contains-hidden-drug-ingredient.