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CHAPARRAL MEDICAL GROUP INC
NPI 1114989241
Internal Medicine - Endocrinology, Diabetes & Metabolism in Pomona, CA

Active since April 04, 2006
1904 N ORANGE GROVE AVE, CHAPARRAL MEDICAL GROUP, POMONA, CA 91767(909) 469-1823(909) 469-1827 Get Directions Write a Review

NPPES record last updated: March 14, 2022. Verified against the NPPES registry weekly; last sync: November 01, 2026.

About Chaparral Medical Group Inc NPPES

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

CHAPARRAL MEDICAL GROUP INC (NPI 1114989241) is a healthcare organization registered as an endocrinology, diabetes & metabolism in Pomona, California and active in the NPI registry since April 2006. The organization lists Adrienne M Walker, Contracts Administrator, as its authorized official.

NPPES Registry Identity

NPI1114989241
Entity TypeOrganization
Primary Taxonomy207RE0101X
Legal Business NameCHAPARRAL MEDICAL GROUP INC
Location Address1904 N ORANGE GROVE AVE, CHAPARRAL MEDICAL GROUPPomona, CA 91767-3008
Mailing Address840 Towne Center Dr, Administrative ResourcesPomona, CA 91767-5900 · (909) 398-1550 · Fax (909) 398-1573
Phone(909) 469-1823
Fax(909) 469-1827
Organization SubpartNo
Authorized OfficialAdrienne M WalkerContracts Administrator · (909) 398-1550
Enumeration DateApril 4, 2006
Last NPPES UpdateMarch 14, 2022
NPPES CertifiedMarch 14, 2022
✔ NPI 1114989241 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses 3

★ Primary SpecialtyInternal Medicine · Endocrinology, Diabetes & MetabolismAllopathic & Osteopathic Physicians
Taxonomy Code207RE0101X
Definition
An internist who concentrates on disorders of the internal (endocrine) glands such as the thyroid and adrenal glands. This specialist also deals with disorders such as diabetes, metabolic and nutritional disorders, obesity, pituitary diseases and menstrual and sexual problems.
Also ListedDietitian, RegisteredTaxonomy 133V00000X
Also ListedInternal MedicineTaxonomy 207R00000X
1904 N ORANGE GROVE AVE, Pomona, CA 91767
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Other Identifiers 1

MedicaidGR0052958CA

Group Practice 1

Group TaxonomyThis provider is a business group of one or more individual practitioners, who practice with different areas of specialization.193200000X MULTI-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)

Chaparral Medical Group Inc is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).

Clinicians Billing Medicare Through This Organization

114

Medicare enrollment records show 114 clinicians reassign Medicare billing to Chaparral Medical Group Inc, which bills Medicare for the services they deliver. Of these, 18 practice at this address and 80 within 10 miles. Listed here are the 20 practicing nearest to this location.

Clinicians by Medicare Specialty 28

Internal Medicine29
Cardiovascular Disease (Cardiology)11
Nurse Practitioner9
Family Practice7
Pulmonary Disease7
Endocrinology5
Gastroenterology5
Dermatology4
20 other specialties37

Nearest to this location (20)

See all 114
Prasad Jeereddi, MD
Endocrinology
NPI 1821058470
1904 N ORANGE GROVE AVE
Pomona, CA 91767
(909) 469-1823
✔ PECOS✔ Accepts MedicareSame address
Rita Pradhan, MD
Endocrinology
NPI 1336117738
1904 N ORANGE GROVE AVE CHAPARRAL MEDICAL GROUP
Pomona, CA 91767
(909) 469-1823
✔ PECOS✔ Accepts MedicareSame address
Jaffar Tremazi, MD
Rheumatology
NPI 1649248782
1904 N ORANGE GROVE AVE
Pomona, CA 91767
(909) 469-1823
✔ PECOS✔ Accepts MedicareSame address
Daryoosh Valamanesh, M.D.
Internal Medicine
NPI 1205804671
1904 N ORANGE GROVE AVE
Pomona, CA 91767
(909) 469-1823
✔ PECOS✔ Accepts MedicareSame address
Gurbinder Sadana, M.D.
Pulmonary Disease
NPI 1205898327
1940 N. ORANGE GROVE SUITE A
Pomona, CA 91767
(909) 865-6900
✔ PECOS✔ Accepts MedicareSame address
Rakesh Sinha, M.B.B.S., M.D.
Pulmonary Disease
NPI 1306006358
1940 N ORANGE GROVE AVE STE A
Pomona, CA 91767
(909) 865-6900
✔ PECOS✔ Accepts MedicareSame address
Nadir Eltahir, MD
Pulmonary Disease
NPI 1053389338
1940 N ORANGE GROVE AVE
Pomona, CA 91767
(909) 865-6900
✔ PECOS✔ Accepts MedicareSame address
Anthony Gan
Internal Medicine
NPI 1902223092
1940 N ORANGE GROVE AVE STE A
Pomona, CA 91767
(909) 865-6900
✔ PECOS✔ Accepts MedicareSame address
Guangqiang Gao, M.D
Cardiac Surgery
NPI 1124322086
1940 N ORANGE GROVE AVE STE B
Pomona, CA 91767
(909) 865-9099
✔ PECOS✔ Accepts MedicareSame address
Joseph Gordon, M.D.
Internal Medicine
NPI 1811243652
1940 N ORANGE GROVE AVE
Pomona, CA 91767
(909) 865-6900
✔ PECOS✔ Accepts MedicareSame address
Dallis Ngo, D.O., M.S.
Pulmonary Disease
NPI 1174055149
1940 N ORANGE GROVE AVE STE A
Pomona, CA 91767
(909) 865-6900
✔ PECOS✔ Accepts MedicareSame address
Derrick Raptis, M.D.
Pulmonary Disease
NPI 1679749683
1940 N ORANGE GROVE AVE STE A
Pomona, CA 91767
(909) 865-6900
✔ PECOS✔ Accepts MedicareSame address
Nathaniel Soriano, M.D.
Internal Medicine
NPI 1679890271
1940 N. ORANGE GROVE AVE SUITE A
Pomona, CA 91767
(909) 865-6900
✔ PECOS✔ Accepts MedicareSame address
Sumi Felix, MD
Internal Medicine
NPI 1053576801
1880 N ORANGE GROVE AVE
Pomona, CA 91767
(909) 620-7200
✔ PECOSSame address
Francis Mendez Munduate, M.D.
Internal Medicine
NPI 1659614121
1880 N ORANGE GROVE AVE
Pomona, CA 91767
(909) 630-7158
✔ PECOS✔ Accepts MedicareSame address
Nancy Ramirez, NP-C
Nurse Practitioner
NPI 1992185847
1880 N ORANGE GROVE AVE
Pomona, CA 91767
(909) 620-7200
✔ PECOSSame address
Lay Tun, M.D
Internal Medicine
NPI 1326232992
1880 N ORANGE GROVE AVE
Pomona, CA 91767
(909) 630-7158
✔ PECOS✔ Accepts MedicareSame address
Parveen Virani, MD
Internal Medicine
NPI 1568457844
1880 N ORANGE GROVE AVE
Pomona, CA 91767
(909) 620-7200
✔ PECOSSame address
Praveena Jeereddi, MD
Geriatric Medicine
NPI 1346218740
1880 N ORANGE GROVE AVE
Pomona, CA 91767
(909) 620-7200
✔ PECOS✔ Accepts Medicare0.1 mi
Ewa Konca, MD
Endocrinology
NPI 1134197528
1880 N ORANGE GROVE AVE
Pomona, CA 91767
(909) 620-7200
✔ PECOS✔ Accepts Medicare0.1 mi
See all 114 clinicians

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

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 Chaparral Medical Group Inc's NPI number?

The NPI number for Chaparral Medical Group Inc is 1114989241. It was assigned to this organization in the NPPES registry on April 4, 2006.

Where is Chaparral Medical Group Inc located?

Chaparral Medical Group Inc is located at 1904 N Orange Grove Ave Chaparral Medical Group, Pomona, CA 91767. The listed phone number is (909) 469-1823.

What is Chaparral Medical Group Inc's specialty?

The primary specialty registered for this NPI is Internal Medicine, specializing in Endocrinology, Diabetes & Metabolism, with taxonomy code 207RE0101X.

Is Chaparral Medical Group Inc enrolled in Medicare?

Yes. Chaparral Medical Group Inc is registered in the Medicare PECOS enrollment system.

How many clinicians bill Medicare through Chaparral Medical Group Inc?

According to the CMS Revalidation Reassignment List (October 2026 release), 114 clinicians in 28 Medicare specialties reassign their Medicare billing to Chaparral Medical Group Inc. 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 Internal Medicine (29), Cardiovascular Disease (Cardiology) (11) and Nurse Practitioner (9). Of these, 18 practice at this address and 80 within 10 miles. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.

When was this NPI record last updated?

The NPPES record for Chaparral Medical Group Inc was last updated on March 14, 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.