Theophylline USP Grade from Mexico
Theophylline is a methylxanthine drug and bronchodilator, a purine derivative with fused heterocyclic nitrogen rings fitting 2933 classification. Specified in U.S. note 3 to section VI for this subheading. Used in respiratory medications and as chemical intermediate.
Duty Rate — Mexico → United States
100%
Rate breakdown
9903.04.6093.5%Pharmaceuticals Annex IV: patented pharma articles — 100% floor rate
9903.05.900%Articles already subject to Section 232 (steel/aluminum/copper + derivatives, autos + parts, wood, medium/heavy vehicles + parts, semiconductors, patented pharma) — U.S. note 52(f)
Import Tips
• Submit USP certificate and HPLC chromatograms verifying identity and impurity profile
• Declare therapeutic chemical status to prevent misclassification as finished dosage
• Comply with FDA prior notice requirements for bulk pharmaceutical chemicals