The letters were issued to Hopewell Essential Oils and Santiste Labs over claims on their websites that their products bolster the body's immune system against the novel coronavirus or alleviate the symptoms of COVID-19. There are currently no FDA-approved products to prevent or treat COVID-19 and the warnings were part of the FDA's efforts to protect consumers during the pandemic.

Hopewell offers essential oils and herbal products for sale in the U.S. According to the FDA, the company posted misleading claims that the products are safe and/or effective for the prevention and treatment of COVID-19 by way of boosting the body's immune response.

Santiste sells transdermal patches that claim to "boost your immune system and provide antiviral support all day, using all-natural ingredients," according to the agency.

From the time of issuance, the companies were given 48 hours to correct the violations.

The FDA is advising consumers to not purchase or use products that have not been approved, cleared, or authorized by the FDA. The FDA has compiled a list of firms and websites that have been issued warning letters from the FDA concerning the sale and distribution of COVID-19 related products in violation of the Federal Food, Drug, and Cosmetic Act. The Federal Trade Commission is also taking action to protect consumers and businesses against coronavirus scams. More information can be found on the FTC's coronavirus page.