L-Tryptophan from Mexico
L-Tryptophan is an essential amino acid with an indole ring containing oxygen-function characteristics, classified under HTS 2922.49.4950. Used in sleep supplements, mood regulation products, and as a precursor for serotonin.
Duty Rate — Mexico → United States
110%
Rate breakdown
9903.04.6095.8%Except as provided in heading 9903.04.61, patented pharmaceutical articles as provided for in subdivisions (c) and (d) of U.S. note 40 to this subchapter
9903.05.5510%Except for products described in headings 9903.05.85–9903.05.92 and 9903.05.94, articles the product of Mexico, as provided for in U.S. note 52 to this subchapter
Import Tips
• Provide third-party lab tests for eosinophilia-myalgia syndrome contaminants from historical issues
• Declare tryptophan content >98% with HPLC chromatograms for CBP verification
• Use food-grade packaging to avoid pharmaceutical classification scrutiny