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ISABEL S OBRIEN MD, MPH
NPI 1386387488
Emergency Medicine - Hospice and Palliative Medicine in San Francisco, CA

Active since April 16, 2022PECOS Enrolled
521 PARNASSUS AVE, BOX 0125, SAN FRANCISCO, CA 94143(415) 476-4838 Get Directions Write a Review

NPPES record last updated: June 17, 2025. Verified against the NPPES registry weekly; last sync: November 01, 2026.

Record update history: Jun 17, 2025, Apr 16, 2022 (2 updates tracked since 2022).

About Isabel S Obrien Md, Mph NPPES

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

ISABEL S OBRIEN MD, MPH (NPI 1386387488) is an individual hospice and palliative medicine provider in San Francisco, California, licensed in California (A202699) and active in the NPI registry since April 2022. She is enrolled in Medicare PECOS and is a graduate of Tufts University School Of Medicine (2022).

NPPES Registry Identity

NPI1386387488
Entity TypeIndividualFemale
Primary Taxonomy207PH0002X
Provider Legal NameISABEL S OBRIENCredential: MD, MPH
Location Address521 PARNASSUS AVE, BOX 0125San Francisco, CA 94143
Mailing Address521 Parnassus Ave, Box 0125San Francisco, CA 94143
Phone(415) 476-4838
Sole ProprietorNo
Medical School CMSTufts University School Of MedicineGraduated 2022
Enumeration DateApril 16, 2022
Last NPPES UpdateJune 17, 20252 updates tracked since enumeration
NPPES CertifiedJune 17, 2025
✔ NPI 1386387488 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses 3

★ Primary SpecialtyEmergency Medicine · Hospice and Palliative MedicineAllopathic & Osteopathic Physicians
Taxonomy Code207PH0002X
License✔ Licensed in CA · A202699
Definition
An emergency medicine physician with special knowledge and skills to prevent and relieve the suffering experienced by patients with life-limiting illnesses. This specialist works with an interdisciplinary hospice or palliative care team to maximize quality of life while addressing physical, psychological, social and spiritual needs of both patient and family throughout the course of the disease, through the dying process, and beyond for the family. This specialist has expertise in the assessment of patients with advanced disease; the relief of distressing symptoms; the coordination of interdisciplinary patient and family-centered care in diverse venues; the use of specialized care systems including hospice; the management of the imminently dying patient; and legal and ethical decision making in end-of-life care.
Also ListedEmergency MedicineTaxonomy 207P00000X · License 72964 (TN)
Also ListedStudent in an Organized Health Care Education/Training ProgramTaxonomy 390200000X
521 PARNASSUS AVE, BOX 0125, San Francisco, CA 94143
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Accepted Insurance

The full list of accepted plans is on the Insurance tab. Issuers include BlueCross BlueShield of Tennessee.Insurance ›

Medicare Participation & PECOS CMS

Medicare enrollment, assignment, billing reassignment, and ordering and referring status from CMS.

Medicare Enrollment Status

✔

Enrolled in Medicare (PECOS)

Isabel S Obrien Md, Mph is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).

PECOS PAC ID2769869866
PECOS Enrollment IDI20260115002100
Eligible to Order & Refer✔ Part B Labs & Imaging✔ Durable Medical Equipment✔ Home Health Agency✔ Power Mobility DevicesPer the CMS Ordering and Referring file. Eligibility means Medicare pays claims that this provider orders or refers for these categories.

Medicare Billing Reassignments

3

Medicare enrollment records show Isabel Obrien reassigns Medicare billing to 3 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.

Desert Group Services, PC
427 mi
Geriatric Medicine
6722 WHITE FEATHER RD
Joshua Tree, CA 92252
  • Reassigned Medicare billing, California enrollment
  • 25 clinicians in this Medicare group
NPI 1932760337 (706) 366-1500
Tennessee River Physicians, PLLC
2,055 mi
Emergency Medicine
16931 RANKIN AVE
Dunlap, TN 37327
  • Reassigned Medicare billing, Tennessee enrollment
  • 183 clinicians in this Medicare group
NPI 1699212761 (423) 949-2000
Erlanger Health
2,067 mi
Internal Medicine
979 E 3RD ST STE A440
Chattanooga, TN 37403
  • Reassigned Medicare billing, Tennessee enrollment
  • 679 clinicians in this Medicare group
NPI 1477256303 (423) 778-2867

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

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 94143 ZIP code area, from fee-for-service claims. These are area statistics, not this provider’s prices; actual charges vary by service and coverage.

New Patient
$104.51 typical visit price
range $69.00 – $202.35
Typical copayment $26.12 (range $17.25 – $50.58)
Most-billed visit code 99203
Established Patient
$119.48 typical visit price
range $23.44 – $166.46
Typical copayment $29.87 (range $5.86 – $41.61)
Most-billed visit code 99214
Amounts reflect what Medicare beneficiaries in this ZIP area are typically charged for office visits. Patients with other coverage should check their individual plans.

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 Isabel Obrien's NPI number?

The NPI number for Isabel Obrien is 1386387488. It was assigned to this individual provider in the NPPES registry on April 16, 2022.

Where is Isabel Obrien located?

Isabel Obrien practices at 521 Parnassus Ave, Box 0125, San Francisco, CA 94143. The listed phone number is (415) 476-4838.

What is Isabel Obrien's specialty?

The primary specialty registered for this NPI is Emergency Medicine, specializing in Hospice and Palliative Medicine, with taxonomy code 207PH0002X.

Is Isabel Obrien enrolled in Medicare?

Yes. Isabel Obrien is registered in the Medicare PECOS enrollment system.

Which organizations bill Medicare for Isabel Obrien's services?

According to the CMS Revalidation Reassignment List (October 2026 release), Isabel Obrien reassigns Medicare benefits to 3 organizations: Desert Group Services, PC (Joshua Tree, CA), Tennessee River Physicians, PLLC (Dunlap, TN) and Erlanger Health (Chattanooga, TN). Each 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 Isabel Obrien's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.

What insurance does Isabel Obrien accept?

Health plans from BlueCross BlueShield of Tennessee list Isabel Obrien as in-network in at least one marketplace plan. Coverage varies by plan and year; verify with the insurer or the provider before a visit.

When was this NPI record last updated?

The NPPES record for Isabel Obrien was last updated on June 17, 2025. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 16 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.