The pharmacological profile of this compound has not been examined ad finem, so it is potentially dangerous for consumers. The contents listed on the packaging do not include this compound, so consumers are unaware of this potential threat to their health and life. The material examined was in capsules packaged in so-called “blisters” of aluminum having printed graphic characters in blue and violet colors and the inscription “Dai Dai Hua Jiao Nang.” After isolating the component by column chromatography and performing a series of examinations using infrared spectroscopy as well as proton and carbon magnetic resonance, the unknown component was identified as N-desmethylsibutramine hydrochloride. The correctness of the structure determination was confirmed by synthesis of the reference material. The presence of this compound constitutes the manufacturers’ unrevealed modification in the content of “herbal” slimming aids named Meizitang and LiDA. This paper provides detailed descriptions of the materials, equipment, and methods used in the analysis. 11 figures and 17 references