DR. DENNIS ARTHUR O'BRIEN M.D.
NPI 1043250079
Psychiatry & Neurology - Psychiatry in Riverdale, GA

Q: What is Dennis O'brien's NPI number?

The NPI number for Dennis O'brien is 1043250079. It was assigned to this individual provider in the NPPES registry on June 7, 2006.

Q: What is Dennis O'brien's specialty?

The primary specialty registered for this NPI is Psychiatry & Neurology, specializing in Psychiatry, with taxonomy code 2084P0800X.

Q: When was this NPI record last updated?

The NPPES record for Dennis O'brien was last updated on June 8, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 2 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.

Active since June 07, 2006PECOS Enrolled

223 MEDICAL CENTER DR, RIVERDALE, GA 30274(770) 991-8500 Get Directions Write a Review

NPPES record last updated: June 8, 2026. Verified against the NPPES registry weekly; last sync: August 09, 2026.

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About Dr. Dennis Arthur O'brien M.d. NPPES

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

DR. DENNIS ARTHUR O'BRIEN M.D. (NPI 1043250079) is an individual psychiatry provider in Riverdale, Georgia, licensed in California (C161834) and active in the NPI registry since June 2006. He is enrolled in Medicare PECOS.

NPPES Registry Identity

NPI1043250079

Entity TypeIndividualMale

Primary Taxonomy2084P0800X

Provider Legal NameDR. DENNIS ARTHUR O'BRIENCredential: M.D.

Location Address223 MEDICAL CENTER DRRiverdale, GA 30274-2640

Mailing Address5325 Broder BlvdDublin, CA 94568-3309

Phone(770) 991-8500

Sole ProprietorYes

Enumeration DateJune 7, 2006

Last NPPES UpdateJune 8, 2026

NPPES CertifiedJune 8, 2026

✔ NPI 1043250079 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyPsychiatry & Neurology · PsychiatryAllopathic & Osteopathic Physicians

Taxonomy Code2084P0800X

Licenses✔ Licensed in CA · C161834✔ Licensed in GA · 025893

Definition

A Psychiatrist specializes in the prevention, diagnosis, and treatment of mental disorders, emotional disorders, psychotic disorders, mood disorders, anxiety disorders, substance-related disorders, sexual and gender identity disorders and adjustment disorders. Biologic, psychological, and social components of illnesses are explored and understood in treatment of the whole person. Tools used may include diagnostic laboratory tests, prescribed medications, evaluation and treatment of psychological and interpersonal problems with individuals and families, and intervention for coping with stress, crises, and other problems.

223 MEDICAL CENTER DR, Riverdale, GA 30274

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Other Identifiers 1

Medicaid000483348AGA

Medicare Participation & PECOS CMS

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

Medicare Enrollment Status

✔

Enrolled in Medicare (PECOS)

Dr. Dennis Arthur O'brien M.d. is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).

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 2

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.

Established patient office or other outpatient visit with low level od decision making, if using time, 20 minutes or more 99213

This is a routine visit for patients who have already been seen by the healthcare provider. During this approximately 20-29 minute appointment, your health status will be evaluated and any necessary treatments or tests will be discussed. It's a chance to address any health concerns you may have.

82 services17 patients

Psychiatric diagnostic evaluation with medical services 90792

A psychiatric diagnostic evaluation with medical services is a comprehensive assessment. It includes a detailed examination of your mental health and physical wellbeing, as well as your personal and family history. This evaluation aids in creating an effective treatment plan.

19 services15 patients

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 30274 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

$172.43 typical visit price

range $56.84 – $172.43

Typical copayment $43.10 (range $14.21 – $43.10)

Most-billed visit code 99205

Established Patient

$70.85 typical visit price

range $18.22 – $140.40

Typical copayment $17.71 (range $4.55 – $35.10)

Most-billed visit code 99213

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 5

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

MRS. LAUREN ASHLEY MATTOX PMHNP

Registered Nurse