法律分析：美国食品和药品管理局（FDA）对携带药品入境有严格规定，即使某些药物具有其他国家的医生处方，在其他国家是合法的，只要其未经FDA批准就不能入境。美海关建议入境者仅携带旅途适量必需的药物。如需携带的药物中含有潜在的成瘾性或麻醉剂成分，请务必向海关官员申报携带的所有药物。中国公民入境美国时，请一定避免携带含有麻黄碱、士的宁、吗啡、动物或动物器官等成分的中药或中成药。
法律依据：美国《Unapproved Drugs》
Preserving Patient Access to Medically Necessary Drugs
The agency balances its goal to eliminate unapproved prescription drugs from the market with patient access to medically necessary drugs. FDA carefully considers the possible effects on patient access, including whether any action would likely lead to a disruption in the drug supply, before initiating an action against an unapproved drug.
The agency permits some unapproved drugs to be marketed if they are relied on by health care professionals to treat serious medical conditions when there is no FDA-approved drug to treat the condition or there is insufficient supply of FDA-approved drugs.
FDA Approval is Required by Law
Federal law requires all new drugs in the U.S. be shown to be safe and effective for their intended use prior to marketing. However, some drugs are available in the U.S. even though they have never received the required FDA approval. Many health care professionals and patients are unaware that some of the drugs prescribed are not FDA approved.
FDA permits some unapproved prescription drugs to be marketed if:
the drug is subject to an open drug efficacy study implementation (DESI) program proceeding,
health care professionals rely on the drug to treat serious medical conditions when there is no FDA-approved drug to treat the condition,
there is insufficient supply of an FDA-approved drug.
The law allows some unapproved prescription drugs to be lawfully marketed if they meet the criteria of generally recognized as safe and effective (GRASE) or grandfathered. However, the agency is not aware of any human prescription drug that is lawfully marketed as grandfathered.