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SIENNA MEDICAL CORPORATION
NPI 1174684583
Internal Medicine in Lake Isabella, CA

Active since December 12, 2006
6425 LYNCH CANYON DR, LAKE ISABELLA, CA 93240(760) 379-8630(760) 379-7658 Get Directions Write a Review

NPPES record last updated: May 29, 2026. Verified against the NPPES registry weekly; last sync: October 25, 2026.

Record update history: May 29, 2026, May 22, 2026 (2 updates tracked since 2026).

About Sienna Medical Corporation NPPES

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

SIENNA MEDICAL CORPORATION (NPI 1174684583), doing business as Sienna Wellness Institute, is a healthcare organization registered as an internal medicine in Lake Isabella, California and active in the NPI registry since December 2006. The organization maintains a secondary practice location in Ridgecrest and lists Robert Gross, Owner/president, as its authorized official.

NPPES Registry Identity

NPI1174684583
Entity TypeOrganization
Primary Taxonomy207R00000X
Legal Business NameSIENNA MEDICAL CORPORATION
Location Address6425 LYNCH CANYON DRLake Isabella, CA 93240-9726
Mailing Address6425 Lynch Canyon DrLake Isabella, CA 93240-9726 · (760) 379-8630 · Fax (760) 379-7658
Phone(760) 379-8630
Fax(760) 379-7658
Organization SubpartNo
Authorized OfficialRobert GrossOwner/president · (760) 379-8630
Enumeration DateDecember 12, 2006
Last NPPES UpdateMay 29, 20262 updates tracked since enumeration
NPPES CertifiedMay 29, 2026
✔ NPI 1174684583 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 · 20A7951
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.
6425 LYNCH CANYON DR, Lake Isabella, CA 93240
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Other Names 1

Doing Business AsSienna Wellness Institute

Secondary Practice Location 1

Location 11535 N China Lake Blvd Ste BRidgecrest, CA 93555-2667 · Phone (760) 379-8630 ext. 27 · Fax (760) 379-7658

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)

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

Clinicians Billing Medicare Through This Organization

4

Medicare enrollment records show 4 clinicians reassign Medicare billing to Sienna Medical Corporation, which bills Medicare for the services they deliver. Of these, 1 practice at this address and 2 within 10 miles. They are listed nearest first.

Clinicians, nearest first (4)

Gary Finstad, M.D.
Internal Medicine
NPI 1184763633
6425 LYNCH CANYON DR
Lake Isabella, CA 93240
(760) 379-8630
✔ PECOS✔ Accepts MedicareSame address
Robert Gross, DO
Internal Medicine
NPI 1396827358
6425 LYNCH CANYON DR
Lake Isabella, CA 93240
(760) 379-8630
✔ PECOS✔ Accepts Medicare0.1 mi
Todd Rowland, MSN, RN, FNP-C, CEN
Nurse Practitioner
NPI 1104251909
1111 N CHINA LAKE BLVD
Ridgecrest, CA 93555
(760) 499-3855
✔ PECOS41 mi
Ashley Mcquade, FNP-C
Nurse Practitioner
NPI 1417658782
1081 N CHINA LAKE BLVD
Ridgecrest, CA 93555
(760) 446-3591
✔ PECOS✔ Accepts Medicare41 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 Sienna Medical Corporation's NPI number?

The NPI number for Sienna Medical Corporation is 1174684583. It was assigned to this organization in the NPPES registry on December 12, 2006. The provider is doing business as Sienna Wellness Institute.

Where is Sienna Medical Corporation located?

Sienna Medical Corporation is located at 6425 Lynch Canyon Dr, Lake Isabella, CA 93240. The listed phone number is (760) 379-8630.

What is Sienna Medical Corporation's specialty?

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

Is Sienna Medical Corporation enrolled in Medicare?

Yes. Sienna Medical Corporation is registered in the Medicare PECOS enrollment system.

How many clinicians bill Medicare through Sienna Medical Corporation?

According to the CMS Revalidation Reassignment List (October 2026 release), 4 clinicians reassign their Medicare billing to Sienna Medical Corporation, in Internal Medicine and Nurse Practitioner. 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 2 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 Sienna Medical Corporation was last updated on May 29, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 5 months 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.