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MAYSSAM EL NAJJAR
NPI 1821764622
Internal Medicine in Boston, MA

Active since August 20, 2021PECOS Enrolled
736 CAMBRIDGE ST, BOSTON, MA 02135(617) 789-3000 Get Directions Write a Review

NPPES record last updated: June 25, 2025. Verified against the NPPES registry weekly; last sync: August 09, 2026.

Record update history: Jun 25, 2025, Jun 8, 2022, Aug 20, 2021 (3 updates tracked since 2021).

About Mayssam El Najjar NPPES

Official registry information on file with the National Plan and Provider Enumeration System.

MAYSSAM EL NAJJAR (NPI 1821764622) is an individual internal medicine provider in Boston, Massachusetts, licensed in Massachusetts (289754) and active in the NPI registry since August 2021. She is enrolled in Medicare PECOS and maintains a secondary practice location in Baltimore.

NPPES Registry Identity

NPI1821764622
Entity TypeIndividualFemale
Primary Taxonomy207R00000X
Provider Legal NameMAYSSAM EL NAJJAR
Location Address736 CAMBRIDGE STBoston, MA 02135-2907
Mailing Address707 President St Apt 1614Baltimore, MD 21202-4553
Phone(617) 789-3000
Sole ProprietorNo
Enumeration DateAugust 20, 2021
Last NPPES UpdateJune 25, 20253 updates tracked since enumeration
NPPES CertifiedJune 20, 2025
✔ NPI 1821764622 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses 3

★ Primary SpecialtyInternal MedicineAllopathic & Osteopathic Physicians
Taxonomy Code207R00000X
License✔ Licensed in MA · 289754
Definition
A physician who provides long-term, comprehensive care in the office and the hospital, managing both common and complex illness of adolescents, adults and the elderly. Internists are trained in the diagnosis and treatment of cancer, infections and diseases affecting the heart, blood, kidneys, joints and digestive, respiratory and vascular systems. They are also trained in the essentials of primary care internal medicine, which incorporates an understanding of disease prevention, wellness, substance abuse, mental health and effective treatment of common problems of the eyes, ears, skin, nervous system and reproductive organs.
Also ListedCounselorTaxonomy 101Y00000X
Also ListedStudent in an Organized Health Care Education/Training ProgramTaxonomy 390200000X · License 289754 (MA)
736 CAMBRIDGE ST, Boston, MA 02135
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Secondary Practice Location 1

Location 14940 Eastern AveBaltimore, MD 21224-2735 · Phone (410) 550-0100

Other Identifiers 1

Medicaid236MA

Medicare Participation & PECOS CMS

Medicare enrollment, assignment, and ordering and referring status from the CMS PECOS system.

Medicare Enrollment Status

✔

Enrolled in Medicare (PECOS)

Mayssam El Najjar is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).

Eligible to Order & Refer✔ Part B Labs & Imaging✔ Durable Medical Equipment✔ Home Health Agency✔ Power Mobility DevicesPer the CMS Ordering and Referring file. Eligibility means Medicare pays claims that this provider orders or refers for these categories.

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 02135 ZIP code area, from fee-for-service claims. These are area statistics, not this provider’s prices; actual charges vary by service and coverage.

New Patient
$144.11 typical visit price
range $63.72 – $189.86
Typical copayment $36.02 (range $15.93 – $47.46)
Most-billed visit code 99204
Established Patient
$111.18 typical visit price
range $21.07 – $155.29
Typical copayment $27.79 (range $5.26 – $38.82)
Most-billed visit code 99214
Amounts reflect what Medicare beneficiaries in this ZIP area are typically charged for office visits. Patients with other coverage should check their individual plans.

Other Providers at the Same Location NPPES 20

Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.

SOOWHAN LAH M.D.
Internal Medicine
736 CAMBRIDGE ST, INTERNAL MEDICINE RESIDENCY PROGRAM - MAILBOX #13
BOSTON, MA 02135
Suffolk County (503) 886-9722
DR. MAHENDRA CARPEN MD
Internal Medicine (Cardiovascular Disease)
736 CAMBRIDGE ST, DEPT. OF CARDIOLOGY
BRIGHTON, MA 02135
Suffolk County (617) 789-5151
MONIKA BATRA
Psychiatry & Neurology (Psychiatry)
736 CAMBRIDGE ST
BRIGHTON, MA 02135
Suffolk County (617) 789-3000
RONYA OZTURK
Student in an Organized Health Care Education/Training Program
736 CAMBRIDGE ST
BOSTON, MA 02135
Suffolk County (617) 789-3000
ALEXANDER H HU MD
Student in an Organized Health Care Education/Training Program
736 CAMBRIDGE ST
BRIGHTON, MA 02135
Suffolk County (617) 789-3000
DR. ANAS AHMED SAMBAWAH M.D
Student in an Organized Health Care Education/Training Program
736 CAMBRIDGE ST
BRIGHTON, MA 02135
Suffolk County (617) 789-2990
ORFEAS LIANGOS M.D.
Internal Medicine (Nephrology)
736 CAMBRIDGE ST, ST ELIZABETHS MED CTR
BOSTON, MA 02135
Suffolk County (617) 789-3100
LORI H ADCOCK M.D.
Pathology (Anatomic Pathology & Clinical Pathology)
736 CAMBRIDGE ST
BRIGHTON, MA 02135
Suffolk County (617) 789-2740

Frequently Asked Questions NPPES & CMS

Common questions about this NPI record, answered from the official NPPES registry and CMS datasets shown on this page.

What is Mayssam El Najjar's NPI number?

The NPI number for Mayssam El Najjar is 1821764622. It was assigned to this individual provider in the NPPES registry on August 20, 2021.

Where is Mayssam El Najjar located?

Mayssam El Najjar practices at 736 Cambridge St, Boston, MA 02135. The listed phone number is (617) 789-3000.

What is Mayssam El Najjar's specialty?

The primary specialty registered for this NPI is Internal Medicine with taxonomy code 207R00000X.

Is Mayssam El Najjar enrolled in Medicare?

Yes. Mayssam El Najjar is registered in the Medicare PECOS enrollment system.

When was this NPI record last updated?

The NPPES record for Mayssam El Najjar was last updated on June 25, 2025. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 13 months ago. If this record has changed at CMS more recently, you can request an on-demand re-check against the live CMS registry, directly from this page.