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James Stewart Lang, M.D.

Internal Medicine Physician in Chelsea, MA · enumerated 2014.

Data current as of Jul 13, 2026 · sourced from CMS NPPES

National Provider Identifier

1528488798

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Registry record

Entity type Individual (Type 1)
Name James Stewart Lang
Credential M.D.
Sex Male
Practice address 151 Everett Ave, Chelsea, MA, 02150
Phone (617) 889-8520
Fax (617) 889-8571
Enumeration date Apr 25, 2014
Last updated in NPPES Oct 15, 2025

Taxonomy & licenses

207R00000X Internal Medicine Physician Allopathic & Osteopathic Physicians · License 269504 (MA) Primary
207R00000X Internal Medicine Physician Allopathic & Osteopathic Physicians · License MD61493634 (WA) Secondary
MD · Doctor of Medicine: A physician who completed medical school (allopathic medicine), residency training, and state licensure. About the MD credential

What is an NPI number?

A National Provider Identifier (NPI) is a unique 10-digit number that CMS assigns to every U.S. healthcare provider and organization under HIPAA. Type 1 NPIs identify individual providers; Type 2 NPIs identify organizations. The NPI appears on insurance claims, prescriptions, and credentialing paperwork, and never changes, even if the provider moves or changes specialty.

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Frequently asked questions

What is the NPI number for James Lang?
The National Provider Identifier (NPI) for James Lang is 1528488798, a Type 1 (individual) record in the CMS NPPES registry.
Where does James Lang practice?
The practice location on file with NPPES is in Chelsea, MA. Providers can have multiple locations; NPPES lists the primary practice address.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2025-10-15.