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DR. THEODORE ROBERTSON PAK MD, PHD
NPI 1013476100
Internal Medicine - Infectious Disease in Orange, CA

Active since March 18, 2019PECOS EnrolledAccepts Medicare Assignment
101 THE CITY DR S, ORANGE, CA 92868(714) 456-8888 Get Directions Write a Review

NPPES record last updated: January 9, 2026. Verified against the NPPES registry weekly; last sync: August 02, 2026.

Record update history: Jan 9, 2026, Aug 13, 2025, Jul 23, 2024 and 2 more (5 updates tracked since 2019).

About Dr. Theodore Robertson Pak Md, Phd NPPES

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

DR. THEODORE ROBERTSON PAK MD, PHD (NPI 1013476100) is an individual infectious disease provider in Orange, California, licensed in California (A203241) and active in the NPI registry since March 2019. He is enrolled in Medicare PECOS, is affiliated with Massachusetts General Hospital, and is a graduate of Icahn School Of Medicine At Mount Sinai (2019).

NPPES Registry Identity

NPI1013476100
Entity TypeIndividualMale
Primary Taxonomy207RI0200X
Provider Legal NameDR. THEODORE ROBERTSON PAKCredential: MD, PHD
Location Address101 THE CITY DR SOrange, CA 92868-3201
Mailing Address101 The City Dr SOrange, CA 92868-3201 · (714) 456-8888
Phone(714) 456-8888
Sole ProprietorNo
Medical School CMSIcahn School Of Medicine At Mount SinaiGraduated 2019
Enumeration DateMarch 18, 2019
Last NPPES UpdateJanuary 9, 20265 updates tracked since enumeration
NPPES CertifiedJanuary 9, 2026
✔ NPI 1013476100 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses 2

★ Primary SpecialtyInternal Medicine · Infectious DiseaseAllopathic & Osteopathic Physicians
Taxonomy Code207RI0200X
Licenses✔ Licensed in CA · A203241✔ Licensed in MA · 291119
Definition
An internist who deals with infectious diseases of all types and in all organ systems. Conditions requiring selective use of antibiotics call for this special skill. This physician often diagnoses and treats AIDS patients and patients with fevers which have not been explained. Infectious disease specialists may also have expertise in preventive medicine and travel medicine.
Also ListedInternal MedicineTaxonomy 207R00000X · License 291119 (MA)
101 THE CITY DR S, Orange, CA 92868
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Medicare Participation & PECOS CMS

Medicare enrollment, assignment, and ordering and referring status from the CMS PECOS system.

Medicare Enrollment Status

✔

Enrolled in Medicare and accepts Medicare assignment

Dr. Theodore Robertson Pak Md, Phd is registered in PECOS and agrees to accept the Medicare-approved amount as full payment. Medicare patients are not billed beyond the standard deductible and coinsurance.

PECOS PAC ID42549099
PECOS Enrollment IDI20250908002894
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.

Areas of Expertise CMS Part B claims

Services this provider delivered to Medicare fee-for-service patients, from the CMS Medicare utilization data. Higher counts generally reflect more experience with a service; care delivered outside Medicare is not included.

Subsequent hospital care with moderate levelof medical decision making, if using time, at least 50 minutes 99233
Follow-up hospital inpatient care per day typically involves a 35-minute check-up by your healthcare provider. This service includes monitoring your health progress, adjusting your treatment plan if needed, and answering any questions you may have about your condition or care.
28 services11 patients

Hospital Affiliations CMS Care Compare

Hospitals where this provider delivers care, identified from recent Medicare claims and place-of-service records.

Massachusetts General Hospital

Acute Care Hospitals · Boston, MA
5/5 CMS rating
OwnershipVoluntary non-profit - Private
CMS Certification Number220071
Location55 Fruit StreetBoston, MA 02114 · Suffolk County
Emergency services Birthing friendly

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 92868 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
$142.39 typical visit price
range $62.96 – $187.60
Typical copayment $35.59 (range $15.74 – $46.90)
Most-billed visit code 99204
Established Patient
$109.96 typical visit price
range $20.84 – $153.61
Typical copayment $27.49 (range $5.21 – $38.40)
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.

Other Providers at the Same Location NPPES 20

Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.

DR. ANKIT BHUPENDRA PATEL D.O.
Radiology (Diagnostic Radiology)
101 THE CITY DR S
ORANGE, CA 92868
Orange County (714) 456-5113
DR. LAURA CATHERINE SKOCZYLAS MD
Obstetrics & Gynecology
101 THE CITY DR S, BUILDING 56, DEPARTMENT OF OB/GYN
ORANGE, CA 92868
Orange County (714) 456-8224
MICHAEL CHENG DO
Internal Medicine (Rheumatology)
101 THE CITY DR S
ORANGE, CA 92868
Orange County (714) 456-7110
AESTHETIC AND PLASTIC SURGERY INSTITUTE
Plastic Surgery
101 THE CITY DR S
ORANGE, CA 92868
Orange County (714) 456-2986
JOSEPH VILLARREAL M.D.
Emergency Medicine
101 THE CITY DR S, BUILDING 1A, ROOM 1009
ORANGE, CA 92868
Orange County (714) 456-5239
DEMI TRAN
Psychiatry & Neurology (Neurology)
101 THE CITY DR S, CITY TOWER, SUITE 400
ORANGE, CA 92868
Orange County (171) 456-6693
DR. ISABEL CARLTON CLARK M.D.
Surgery (Trauma Surgery)
101 THE CITY DR S
ORANGE, CA 92868
Orange County (714) 456-7890
DYLAN LUKATO
Emergency Medicine
101 THE CITY DR S
ORANGE, CA 92868
Orange County (415) 218-8041

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 Theodore Pak's NPI number?

The NPI number for Theodore Pak is 1013476100. It was assigned to this individual provider in the NPPES registry on March 18, 2019.

Where is Theodore Pak located?

Theodore Pak practices at 101 The City Dr S, Orange, CA 92868. The listed phone number is (714) 456-8888.

What is Theodore Pak's specialty?

The primary specialty registered for this NPI is Internal Medicine, specializing in Infectious Disease, with taxonomy code 207RI0200X.

Is Theodore Pak enrolled in Medicare?

Yes. Theodore Pak is registered in the Medicare PECOS system and accepts Medicare assignment, which means accepting the Medicare-approved amount as payment in full for covered services.

Is Theodore Pak affiliated with any hospitals?

According to CMS data, Theodore Pak is affiliated with Massachusetts General Hospital.

When was this NPI record last updated?

The NPPES record for Theodore Pak was last updated on January 9, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 6 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.