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Naproxen Base from Japan

Naproxen is an NSAID used for pain relief, fever reduction, and inflammation, classified in HTS 2933.99.55 due to its aromatic heterocyclic nitrogen-containing structure. As a bulk pharmaceutical API primarily affecting the CNS, it meets the heading for analgesics and antipyretics.

Duty Rate — Japan → United States

12.5%

Rate breakdown

9903.05.4912.5%Section 301 (forced labor) — Japan (col1 rate < 12.5 percent): MFN < 12.5% → total duty capped at 12.5%

Import Tips

Submit detailed spectral analysis proving aromatic heterocyclic nitrogen hetero-atom(s) for classification

Include stability data as stabilizer additions are allowed per chapter note (f) without reclassification

Watch for pitfalls in ester forms, which classify with the acid per chapter note on esters