DR. LEIGH M FIRN (MD) – Internal Medicine Physician, NPI 1194706507

Internal Medicine Physician

DR. LEIGH M FIRN (MD) is a healthcare provider. based in Cambridge, Massachusetts. specializing in Internal Medicine Physician. They hold the professional credentials MD. They hold a License No. 57872 (MA). The NPI Number for DR. LEIGH M FIRN (MD) is 1194706507

Main info

Male

40 Years Of Experience

Accepts Medicare Assignment

Name

DR. LEIGH M FIRN (MD)

NPI

1194706507

Phone

(617) 253-4988

Address

25 CARLETON STREET

Enumeration Date

11 November 2005

Last Update Date

12 April 2012

Doctor Profile

Medical School Name

UNIVERSITY OF MASSACHUSETTS MEDICAL SCHOOL

Secondary Phone

6172586896

Graduation Year

1986 (40 years ago)

PAC ID

3678510906

Group Practice PAC ID

5597658666

Professional Enrollment ID

I20050408000490

Data current as of

19 May 2026

Profile Insights

NPPES metrics only — not quality of care.

Methodology

Experience54

Completeness75

Years active:20State licenses:1Digital endpointsOther names

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Provider Addresses for DR. LEIGH M FIRN (MD)

E23, 25, Carleton Street, Cambridge, Middlesex County, Massachusetts, 02142, United States
E23
CAMBRIDGE, MA 021394307
Phone: (617) 253-4988
Type: Mailing
77 Massachusetts Ave, Massachusetts Avenue, Central Square, Cambridgeport, Cambridge, Middlesex County, Massachusetts, 02238, United States
MIT E23/225
CAMBRIDGE, MA 021394301
Phone: (617) 253-4909
Type: Location

NPPES updates history

No NPPES updates recorded for this provider.

Prescription Activity

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Open Payments (CMS)

No Open Payments data available for this provider.

This can happen when there are no reportable CMS Open Payments records.

Medicare Enrollment & Revalidation

Source: CMS public data · Not endorsed by CMS ·

Educational use only—not medical, billing, or legal advice.

No Medicare enrollment or revalidation data available for this provider in our database.

Prepare CMS-855 application → · Look up this NPI in PECOS → · Verify on CMS PECOS

Medicare Utilization (FFS)

Source: CMS public data · Not endorsed by CMS · Beneficiary counts under 11 are suppressed in source data ·

Educational use only—not medical, billing, or legal advice.

No Medicare fee-for-service utilization data available for this provider in our database.

Insurance plans in this area (ZIP 02139)

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Provider's Procedures

DR. LEIGH M FIRN (MD) performs procedures in Internal Medicine Physician. See the list of HCPCS codes below.

Specialty	Practice State	HCPCS Code	Description	Service Count	Beneficiary Count
INTERNAL MEDICINE	MA	85610	Blood test, clotting time	81	11
INTERNAL MEDICINE	MA	90670	Pneumococcal vaccine for injection into muscle	13	13

Group practice members

Group practice members are other physicians who share the same Group Practice PAC ID with this doctor. When doctors form a group practice and register in PECOS as a single entity, they receive a shared identification number. This table lists all providers in the same group practice.

PAC ID: 5597658666View full group profile

Name	Specialty	State
MS. LUANNE MARIE OFF (FNP, MSN, MPH, RN)	Nurse Practitioner	MA
IRIS H FOLEY (MD)	Diagnostic Radiology	MA
RALPH L REICHLE (M.D.)	Diagnostic Radiology, Interventional Radiology	MA
MR. EDWARD NICHOLAS WALLER (FNP-BC)	Nurse Practitioner	MA
DR. MICHELE CASSIN (O.D.)	O P T O M E T R Y	MA
MARIE E CAGGIANO (M.D.)	-	MA
PHILIP A ROGOFF (M.D.)	Diagnostic Radiology, Interventional Radiology	MA
ANNA JASONIDES (RD)	-	MA
CHRISTIAN M ROSE (MD, CAQSM)	Family Practice	MA
JENNIFER SHARK (CNM)	Certified Nurse Midwife (Cnm)	NY

Reviews

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Frequently asked questions

What NPI should I save for DR. LEIGH M FIRN (MD)?

Save NPI 1194706507 if you need a stable reference for DR. LEIGH M FIRN (MD).

Is DR. LEIGH M FIRN (MD) currently active in the NPI registry?

CMS-published data lists DR. LEIGH M FIRN (MD) as an active registrant.

What does DR. LEIGH M FIRN (MD) treat or focus on?

Patients typically see DR. LEIGH M FIRN (MD) under the specialty Internal Medicine Physician. Clinical services aligned with this taxonomy classification.

What location shows for DR. LEIGH M FIRN (MD)?

We surface Cambridge, Massachusetts for DR. LEIGH M FIRN (MD) based on available NPPES addresses.

How can I contact DR. LEIGH M FIRN (MD)?

Phone or fax may appear on the official NPI record when supplied — verify before relying on them.