Recently Updated NPI Information — some details in this NPI profile have been updated in the NPI registry within the last 60 days.

DR. EDUARDO GUILLEN MD
NPI 1891315933
Internal Medicine in Oakland, CA

Q: What is Eduardo Guillen's NPI number?

The NPI number for Eduardo Guillen is 1891315933. It was assigned to this individual provider in the NPPES registry on April 18, 2020.

Q: What is Eduardo Guillen's specialty?

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

Q: When was this NPI record last updated?

The NPPES record for Eduardo Guillen was last updated on September 2, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 54 days 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.

Active since April 18, 2020PECOS EnrolledAccepts Medicare Assignment

1411 E 31ST ST FL 2, OAKLAND, CA 94602(510) 437-5039(510) 535-7313 Get Directions Write a Review

NPPES record last updated: September 2, 2026. Verified against the NPPES registry weekly; last sync: October 18, 2026.

Record update history: Sep 2, 2026, Apr 18, 2020 (2 updates tracked since 2020).

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About Dr. Eduardo Guillen Md NPPES

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

DR. EDUARDO GUILLEN MD (NPI 1891315933) is an individual internal medicine provider in Oakland, California, licensed in California (A186129) and active in the NPI registry since April 2020. He is enrolled in Medicare PECOS and is a graduate of Other (2019).

NPPES Registry Identity

NPI1891315933

Entity TypeIndividualMale

Primary Taxonomy207R00000X

Provider Legal NameDR. EDUARDO GUILLENCredential: MD

Location Address1411 E 31ST ST FL 2Oakland, CA 94602-1018

Mailing Address1411 E 31st St Fl 2Oakland, CA 94602-1018 · (510) 437-5039 · Fax (510) 535-7313

Phone(510) 437-5039

Fax(510) 535-7313

Sole ProprietorNo

Medical School CMSOtherGraduated 2019

Enumeration DateApril 18, 2020

Last NPPES UpdateSeptember 2, 20262 updates tracked since enumeration

NPPES CertifiedSeptember 2, 2026

✔ NPI 1891315933 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses 2

★ Primary SpecialtyInternal MedicineAllopathic & Osteopathic Physicians

Taxonomy Code207R00000X

License✔ Licensed in CA · A186129

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 ListedHospitalistTaxonomy 208M00000X · License A186129 (CA)

1411 E 31ST ST FL 2, Oakland, CA 94602

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Medicare Participation & PECOS CMS

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

Medicare Enrollment Status

✔

Enrolled in Medicare and accepts Medicare assignment

Dr. Eduardo Guillen Md 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 ID1759725559

PECOS Enrollment IDI20240220004109

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 Reassignment

Medicare enrollment records show Eduardo Guillen reassigns Medicare billing to 1 organization. The organization bills Medicare for the services this provider delivers there.

Alameda Inpatient Medical Inc

2.7 mi

Internal Medicine

2070 CLINTON AVE
Alameda, CA 94501

Reassigned Medicare billing, California enrollment
22 clinicians in this Medicare group

NPI 1588673750 (510) 814-4397

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

Areas of Expertise CMS Part B claims 5

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.

414 services181 patients

Hospital discharge day management, more than 30 minutes 99239

Hospital discharge day management over 30 minutes involves a detailed process to ensure a smooth transition from hospital to home. It includes final examinations, discussion of your hospital stay, post-discharge instructions, and coordinating follow-up care.

149 services141 patients

Initial hospital care with moderate level of medical decision making, if using time, at least 75 minutes 99223

Initial hospital inpatient care per day, typically 70 minutes, refers to the daily medical service provided to patients admitted to the hospital. This includes a comprehensive evaluation, diagnosis, treatment plan, and monitoring of your health condition. It ensures your well-being during your hospital stay.

82 services78 patients

Subsequent hospital care with moderate levelof medical decision making, if using time, at least 35 minutes 99232

Follow-up hospital inpatient care involves daily check-ups while you're admitted in the hospital. Typically, a healthcare provider spends about 25 minutes each day reviewing your condition, adjusting treatment if needed, and answering any questions you might have.

80 services45 patients

Critical care, first 30-74 minutes 99291

Critical care involves immediate and constant attention by a team of specially-trained health professionals. It's for patients with life-threatening conditions, requiring first 30-74 minutes of intense monitoring and treatment.

53 services26 patients

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 94602 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

$153.83 typical visit price

range $69.00 – $202.35

Typical copayment $38.45 (range $17.25 – $50.58)

Most-billed visit code 99204

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.

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.

MICHAEL UZOMA OHABUGHIRO MD

Internal Medicine