Some of the tactics in the kratom business may sound familiar. They mirror the strategies that were used for another controversial product — synthetic cannabis compounds, or “Spice.”

More than a decade ago, U.S. officials spotted a trend. Importers, court records show, were slipping Spice into the country from China by calling the white chemicals “cosmetics” or “sodium.” Products found at gas stations promised Spice was “herbal incense” or “not for human consumption.”