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Theophylline Monohydrate from Canada

Theophylline monohydrate is a methylxanthine with pyrimidine rings, used in respiratory medications. Classified in HTS 2933.59.70.00 as an aromatic compound per additional U.S. note 3 to section VI. The hydrate form remains a separate chemically defined organic compound.

Duty Rate — Canada → 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

Document water content precisely (monohydrate ~8-9%) to distinguish from anhydrous form

Comply with DEA precursor chemical reporting if applicable for pharma synthesis

Provide GMP manufacturing certificates for API-grade imports