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POTOMAC FAMILY PRACTICE
NPI 1043334410
Family Medicine in Potomac Falls, VA

Active since March 19, 2007CLIA 49D0894322 · Waiver
46165 WESTLAKE DR., STE 120, POTOMAC FALLS, VA 20165(703) 444-3302(703) 444-3240 Get Directions Write a Review

NPPES record last updated: September 27, 2022. Verified against the NPPES registry weekly; last sync: October 18, 2026.

Record update history: Sep 27, 2022, Mar 13, 2022, Aug 10, 2021 (3 updates tracked since 2021).

About Potomac Family Practice NPPES

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

POTOMAC FAMILY PRACTICE (NPI 1043334410) is a healthcare organization registered as a family medicine in Potomac Falls, Virginia and active in the NPI registry since March 2007. The organization holds a CLIA Waiver certificate valid through April 25, 2027 and lists Mary Beth Tamasy, Ceo, as its authorized official.

NPPES Registry Identity

NPI1043334410
Entity TypeOrganization
Primary Taxonomy207Q00000X
Legal Business NameLOUDOUN MEDICAL GROUP, PC
Location Address46165 WESTLAKE DR., STE 120Potomac Falls, VA 20165-5872
Mailing Address224-d Cornwall Street, Nw, Suite 403Leesburg, VA 20176-2704 · (703) 737-6010 · Fax (571) 291-9786
Phone(703) 444-3302
Fax(703) 444-3240
Organization SubpartYes
Authorized OfficialMary Beth TamasyCeo · (703) 737-6010
Enumeration DateMarch 19, 2007
Last NPPES UpdateSeptember 27, 20223 updates tracked since enumeration
NPPES CertifiedSeptember 27, 2022
✔ NPI 1043334410 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyFamily MedicineAllopathic & Osteopathic Physicians
Taxonomy Code207Q00000X
Definition
Family Medicine is the medical specialty which is concerned with the total health care of the individual and the family. It is the specialty in breadth which integrates the biological, clinical, and behavioral sciences. The scope of family medicine is not limited by age, sex, organ system, or disease entity.
46165 WESTLAKE DR., STE 120, Potomac Falls, VA 20165
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Other Names 1

Doing Business AsPotomac Family Practice

Group Practice 1

Group TaxonomyThis provdier is a business group of one or more individual practitioners, all of who practice with the same area of specialization.193400000X SINGLE SPECIALTY GROUP

Medicare Participation & PECOS CMS

Medicare enrollment and the clinicians who bill Medicare through this organization, from CMS.

Medicare Enrollment Status

✔

Enrolled in Medicare (PECOS)

Potomac Family Practice is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).

Clinicians Billing Medicare Through This Organization

334

Medicare enrollment records show 334 clinicians reassign Medicare billing to Potomac Family Practice, which bills Medicare for the services they deliver. Of these, 1 practice at this address and 195 within 10 miles. Listed here are the 20 practicing nearest to this location.

Clinicians by Medicare Specialty 36

Nurse Practitioner93
Family Practice29
Internal Medicine27
Diagnostic Radiology25
Certified Nurse Midwife (CNM)16
Obstetrics/Gynecology14
Podiatry14
Urology13
28 other specialties103

Nearest to this location (20)

See all 334
Nhu-Nga Truong, MD
Family Practice
NPI 1821083486
46165 WESTLAKE DR SUITE 120
Sterling, VA 20165
(703) 444-3302
✔ PECOS✔ Accepts MedicareSame address
Nisha Chand, MD
Internal Medicine
NPI 1912938762
46169 WESTLAKE DR STE 200
Sterling, VA 20165
(703) 378-1734
✔ PECOS✔ Accepts Medicare0.1 mi
Chanpreet Kataria
Optometry
NPI 1922615103
21475 RIDGETOP CIR STE 300
Sterling, VA 20166
(703) 430-4400
✔ PECOS✔ Accepts Medicare0.3 mi
Vishakha Nabar
Physical Therapist in Private Practice
NPI 1922347236
21475 RIDGETOP CIR STE 260
Sterling, VA 20166
(703) 444-5000
✔ Accepts Medicare0.3 mi
Ayman Boutros, M.D.
Ophthalmology
NPI 1366530131
21475 RIDGETOP CIR SUITE 300
Sterling, VA 20166
(703) 430-4400
✔ PECOS✔ Accepts Medicare0.3 mi
Renata Raeder, O.D.
Optometry
NPI 1699857003
21475 RIDGETOP CIRCLE SUITE 300
Sterling, VA 20166
(703) 430-4400
✔ PECOS0.3 mi
Darrell Reisner, M.D.
Ophthalmology
NPI 1912095019
21475 RIDGETOP CIR STE 300
Sterling, VA 20166
(703) 430-4400
✔ PECOS✔ Accepts Medicare0.3 mi
Annemarie Spooner, MD
Obstetrics/Gynecology
NPI 1982672747
21475 RIDGETOP CIRCLE, SUITE 210
Sterling, VA 20166
(703) 858-2811
✔ PECOS0.3 mi
Dian Yu, M.D.
Ophthalmology
NPI 1639527682
21475 RIDGETOP CIRCLE, SUITE 300
Sterling, VA 20166
(703) 430-4400
✔ PECOS✔ Accepts Medicare0.3 mi
Deena Tailor, OD
Optometry
NPI 1104356815
21475 RIDGETOP CIR STE 300
Sterling, VA 20166
(703) 430-4400
✔ PECOS✔ Accepts Medicare0.3 mi
Arvinder Chawla, M.D.
Internal Medicine
NPI 1346253002
21495 RIDGETOP CIRCLE SUITE 102
Sterling, VA 20166
(571) 313-1980
✔ PECOS✔ Accepts Medicare0.3 mi
Rajeev Khanna, M.D.
Internal Medicine
NPI 1609886712
21495 RIDGETOP CIR SUITE 102
Sterling, VA 20166
(571) 313-1980
✔ PECOS✔ Accepts Medicare0.3 mi
Hope Marshall, CANP
Nurse Practitioner
NPI 1831182484
2 PIDGEON HILL DR STE 400
Sterling, VA 20165
(703) 430-7090
✔ PECOS0.4 mi
Sarah Fletcher, MD
Family Practice
NPI 1184610578
21135 WHITFIELD PL STE 107
Sterling, VA 20165
(703) 421-7000
✔ PECOS0.5 mi
Ricardo Ferreira Lopez, MD
Family Practice
NPI 1437218799
2 PIDGEON HILL DRIVE, SUITE 400
Sterling, VA 20165
(703) 430-7090
✔ PECOS✔ Accepts Medicare0.6 mi
Svetlana Nakatis, M.D.
Family Practice
NPI 1134143753
2 PIDGEON HILL DRIVE, SUITE 400
Sterling, VA 20165
(703) 430-7090
✔ PECOS✔ Accepts Medicare0.6 mi
Mark Shasti, MD
Orthopedic Surgery
NPI 1295078848
21351 GENTRY DR STE 125
Sterling, VA 20166
(703) 774-3132
✔ PECOS✔ Accepts Medicare0.7 mi
Erin Collier, NP
Nurse Practitioner
NPI 1356670541
46440 BENEDICT DR SUITE 107
Sterling, VA 20164
(703) 450-1125
✔ PECOS0.9 mi
Kimberly Kolb, DO
Pediatric Medicine
NPI 1396740676
46440 BENEDICT DR STE 207
Sterling, VA 20164
(703) 444-2100
✔ PECOS0.9 mi
Laurel Blymyer, FNP-C
Nurse Practitioner
NPI 1124334750
46440 BENEDICT DRIVE, SUITE 107
Sterling, VA 20164
(703) 450-1125
✔ PECOS✔ Accepts Medicare0.9 mi
See all 334 clinicians

Source: CMS Revalidation Reassignment List, October 2026 release. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.

CLIA Laboratory Certificates CMS CLIA

Laboratory certificates issued under the Clinical Laboratory Improvement Amendments (CLIA) program, which sets federal quality standards for human laboratory testing in the United States. There is no official CMS crosswalk between CLIA and NPI numbers; these certificates are associated with this NPI by matching facility names, locations and phone numbers in the CMS CLIA registry.

Certificate of Waiver 49D0894322

Potomac Family Practice · Potomac Falls, VA
Active · expires Apr 25, 2027
CLIA Number49D0894322
Laboratory TypePhysician Office
Certificate Effective DateApril 26, 2025
Certificate Expiration DateApril 25, 2027
Laboratory DirectorNhu Nga Truong MD
Laboratory Phone(703) 444-3302
Laboratory LocationPotomac Family Practice46165 Westlake Drive - Suite 120, Potomac Falls, VA 20165
CLIA data matches this NPI record on: Address Name Phone
This certificate is issued to a laboratory to perform only waived tests.

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 Loudoun Medical Group, PC's NPI number?

The NPI number for Loudoun Medical Group, PC is 1043334410. It was assigned to this organization in the NPPES registry on March 19, 2007. The provider is doing business as Potomac Family Practice.

Where is Loudoun Medical Group, PC located?

Loudoun Medical Group, PC is located at 46165 Westlake Dr., Ste 120, Potomac Falls, VA 20165. The listed phone number is (703) 444-3302.

What is Loudoun Medical Group, PC's specialty?

The primary specialty registered for this NPI is Family Medicine with taxonomy code 207Q00000X.

Is Loudoun Medical Group, PC enrolled in Medicare?

Yes. Loudoun Medical Group, PC is registered in the Medicare PECOS enrollment system.

How many clinicians bill Medicare through Loudoun Medical Group, PC?

According to the CMS Revalidation Reassignment List (October 2026 release), 334 clinicians in 36 Medicare specialties reassign their Medicare billing to Loudoun Medical Group, PC. A reassignment is filed with Medicare on form CMS-855R, signed by both the clinician and the organization, and lets the organization bill Medicare and receive payment for the clinician's services. The largest specialties are Nurse Practitioner (93), Family Practice (29) and Internal Medicine (27). Of these, 1 practice at this address and 195 within 10 miles. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.

Does Loudoun Medical Group, PC hold a CLIA laboratory certificate?

Yes. A Certificate of Waiver (number 49D0894322) is associated with this NPI, valid through April 25, 2027. CLIA certificates authorize laboratory testing under the federal Clinical Laboratory Improvement Amendments program.

When was this NPI record last updated?

The NPPES record for Loudoun Medical Group, PC was last updated on September 27, 2022. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 4 years 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.