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HUAN C GUU MD A PROFESSIONAL CORPORATION
NPI 1851550859
Internal Medicine in Mission Viejo, CA

Active since June 04, 2008
27700 MEDICAL CENTER RD, MISSION VIEJO, CA 92691(949) 500-8589 Get Directions Write a Review

NPPES record last updated: March 31, 2009. Verified against the NPPES registry weekly; last sync: October 18, 2026.

About Huan C Guu Md A Professional Corporation NPPES

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

HUAN C GUU MD A PROFESSIONAL CORPORATION (NPI 1851550859) is a healthcare organization registered as an internal medicine in Mission Viejo, California and active in the NPI registry since June 2008. The organization lists Huan C Guu, President, as its authorized official.

NPPES Registry Identity

NPI1851550859
Entity TypeOrganization
Primary Taxonomy207R00000X
Legal Business NameHUAN C GUU MD A PROFESSIONAL CORPORATION
Location Address27700 MEDICAL CENTER RDMission Viejo, CA 92691-6426
Mailing Address15333 Culver Dr, Suite 340, Pmb 206Irvine, CA 92604-3078 · (949) 500-8589
Phone(949) 500-8589
Organization SubpartNo
Authorized OfficialHuan C GuuPresident · (949) 500-8589
Enumeration DateJune 4, 2008
Last NPPES UpdateMarch 31, 2009
✔ NPI 1851550859 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyInternal MedicineAllopathic & Osteopathic Physicians
Taxonomy Code207R00000X
License✔ Licensed in CA · A62481
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.
27700 MEDICAL CENTER RD, Mission Viejo, CA 92691
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Other Identifiers 1

Medicare UPINH58207CA

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)

Huan C Guu Md A Professional Corporation is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).

Clinicians Billing Medicare Through This Organization

Medicare enrollment records show 1 clinician reassigns Medicare billing to Huan C Guu MD A Professional Corporation, which bills Medicare for the services this clinician delivers.

Clinician (1)

Huan Guu, M.D.
Internal Medicine
NPI 1952352668
27700 MEDICAL CENTER RD
Mission Viejo, CA 92691
(949) 364-1400
✔ PECOS✔ Accepts MedicareSame address

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 Huan C Guu MD A Professional Corporation's NPI number?

The NPI number for Huan C Guu MD A Professional Corporation is 1851550859. It was assigned to this organization in the NPPES registry on June 4, 2008.

Where is Huan C Guu MD A Professional Corporation located?

Huan C Guu MD A Professional Corporation is located at 27700 Medical Center Rd, Mission Viejo, CA 92691. The listed phone number is (949) 500-8589.

What is Huan C Guu MD A Professional Corporation's specialty?

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

Is Huan C Guu MD A Professional Corporation enrolled in Medicare?

Yes. Huan C Guu MD A Professional Corporation is registered in the Medicare PECOS enrollment system.

How many clinicians bill Medicare through Huan C Guu MD A Professional Corporation?

According to the CMS Revalidation Reassignment List (October 2026 release), 1 clinician (Internal Medicine) reassigns their Medicare billing to Huan C Guu MD A Professional Corporation. 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. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.

When was this NPI record last updated?

The NPPES record for Huan C Guu MD A Professional Corporation was last updated on March 31, 2009. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 17 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.