The Food and Drug Administration has issued a warning for potential customers of a supplement brand known as Neptune's Fix, saying to avoid buying or using these products after receiving reports of dangerous reactions, including seizures, that necessitated hospitalization.

The "FDA is warning consumers to not purchase or use any Neptune's Fix products," the agency said in a statement, adding that the supplements made by Neptune's Fix contain the opioid alternative tianeptine, which is prescribed as an antidepressant in some parts of the world but has not been approved in the United States. The agency describes tianeptine as a "potentially dangerous substance that is not FDA-approved for any medical use but is illegally sold with claims to improve brain function and treat anxiety, depression, pain, opioid use disorder and other conditions."

The warning comes after the FDA "received severe adverse event reports after use of Neptune's Fix products, including seizures and loss of consciousness leading to hospitalization."

The agency states "Consumers who experience a bad reaction to any tianeptine product should seek immediate medical help."

Dalya Ewais, the communications director for the New Jersey Department of Health, told CBS News in an email that the state's poison control center has received almost two dozen calls about tianeptine since June 17 of this year, more than half of which were related to Neptune's Fix products.

"The products were purchased at gas stations, a deli, a vape shop, a tobacco shop, convenience stores, and online. However, gas stations remain the most commonly reported location of purchase," Ewais said.

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