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CENTRAL MEDICAL GROUP
NPI 1841430535
Internal Medicine in Upland, CA

Active since February 20, 2009
350 S EUCLID AVE STE C, UPLAND, CA 91786(909) 591-6575(909) 591-8986 Get Directions Write a Review

NPPES record last updated: July 1, 2024. Verified against the NPPES registry weekly; last sync: November 01, 2026.

Record update history: Jul 1, 2024, Nov 16, 2021, Sep 14, 2017 (3 updates tracked since 2017).

About Central Medical Group NPPES

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

CENTRAL MEDICAL GROUP (NPI 1841430535) is a healthcare organization registered as an internal medicine in Upland, California and active in the NPI registry since February 2009. The organization lists Nicolaas M Grobler, President/owner, as its authorized official.

NPPES Registry Identity

NPI1841430535
Entity TypeOrganization
Primary Taxonomy207R00000X
Legal Business NameGROBLER ENTERPRISES INC
Location Address350 S EUCLID AVE STE CUpland, CA 91786-6665
Mailing Address350 S Euclid Ave Ste CUpland, CA 91786-6665 · (909) 591-6575 · Fax (909) 591-8986
Phone(909) 591-6575
Fax(909) 591-8986
Organization SubpartNo
Authorized OfficialNicolaas M GroblerPresident/owner · (909) 591-6575
Enumeration DateFebruary 20, 2009
Last NPPES UpdateJuly 1, 20243 updates tracked since enumeration
NPPES CertifiedJuly 1, 2024
✔ NPI 1841430535 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 CA · A89047
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 ListedInternal Medicine · Critical Care MedicineTaxonomy 207RC0200X · License A89047 (CA)
Also ListedInternal Medicine · Pulmonary DiseaseTaxonomy 207RP1001X · License A89047 (CA)
350 S EUCLID AVE STE C, Upland, CA 91786
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Other Names 1

Doing Business AsCentral Medical Group

Other Identifiers 2

OtherZZZ58873YCA · Blue Shield
Medicaid1841430535CA

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)

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

Clinicians Billing Medicare Through This Organization

3

Medicare enrollment records show 3 clinicians reassign Medicare billing to Central Medical Group, which bills Medicare for the services they deliver. Of these, 1 practice at this address and 3 within 10 miles. They are listed nearest first.

Clinicians, nearest first (3)

Nicolaas Grobler, MD
Pulmonary Disease
NPI 1720154255
350 S EUCLID AVE STE C
Upland, CA 91786
(909) 591-6575
✔ PECOS✔ Accepts MedicareSame address
Melissa Kramer, FNP
Nurse Practitioner
NPI 1780447706
350 S EUCLID AVE STE C
Upland, CA 91786
(909) 591-6575
✔ PECOS✔ Accepts Medicare0.4 mi
Holly Nikodym, FNP
Nurse Practitioner
NPI 1083306542
901 SAN BERNARDINO RD STE 300
Upland, CA 91786
(909) 579-6753
✔ PECOS✔ Accepts Medicare1.0 mi

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 Grobler Enterprises Inc's NPI number?

The NPI number for Grobler Enterprises Inc is 1841430535. It was assigned to this organization in the NPPES registry on February 20, 2009. The provider is doing business as Central Medical Group.

Where is Grobler Enterprises Inc located?

Grobler Enterprises Inc is located at 350 S Euclid Ave Ste C, Upland, CA 91786. The listed phone number is (909) 591-6575.

What is Grobler Enterprises Inc's specialty?

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

Is Grobler Enterprises Inc enrolled in Medicare?

Yes. Grobler Enterprises Inc is registered in the Medicare PECOS enrollment system.

How many clinicians bill Medicare through Grobler Enterprises Inc?

According to the CMS Revalidation Reassignment List (October 2026 release), 3 clinicians reassign their Medicare billing to Grobler Enterprises Inc, in Nurse Practitioner and Pulmonary Disease. 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. Of these, 1 practice at this address and 3 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 Grobler Enterprises Inc was last updated on July 1, 2024. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 2 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.