Dennis Arthur O'Brien, M.D.

Primary specialty

Psychiatry PhysicianTaxonomy code 2084P0800X

License

C161834 Issued in CA

Practice address

223 Medical Center Dr
Riverdale, GA 30274-2640

Phone

(770) 991-8500

NPI assigned

Jun 7, 2006

Sex

Male

Sole proprietor

Yes

Registry information is reported by the provider to CMS and is not verified. About this source

Specialties & licenses 2

Addresses

Other identifiers 1

Medicare fee-for-service enrollment

Enrolled in GA, CA2 enrollments

Eligible to order & refer

• Part B services: Yes
• Medical equipment: Yes
• Home health: Yes
• Power mobility devices: Yes
• Hospice: Yes

Green means eligible to order or refer.

Enrollment records 2

Medicare enrollment (NPD)

Not enrolled

HHS exclusion list flag

Flagged The directory lists this NPI on an HHS exclusion list. The OIG exclusions file (LEIE) holds no record for this NPI, and the directory does not say which list the flag comes from. How exclusions are shown Confirm with the OIG exclusions search.

Credentials

Doctor of Medicine

State licenses

Practice roles

Locations

Organizations this provider is connected to: Medicare benefit reassignments (the organization bills Medicare for this provider’s services), Care Compare group memberships and National Provider Directory roles.

• Breakthrough Recovery Outreach, LLC

  • Substance Abuse Rehabilitation Facility
  • Atlanta, GA
  • NPI 1982909503
  Medicare reassignment NPD
• Department of Behavioral Health and Developmental Disabilities

  • Psychiatric Hospital
  • Milledgeville, GA
  • NPI 1902030307
  Medicare reassignment NPD
• Shailesh Patel MD LLC

  • Psychiatry Physician
  • Peachtree City, GA
  • NPI 1669765467
  Medicare reassignment NPD
• Uhs of Anchor L.P.

  • Psychiatric Hospital
  • Stockbridge, GA
  • NPI 1952537920
  Medicare reassignment NPD
• Alameda County

  • Community/Behavioral Health Agency
  • Hayward, CA
  • NPI 1780716381
  Medicare reassignment NPD
• Department of Behavioral Health & Developmental Disabilities

  • Psychiatric Hospital
  • Savannah, GA
  • NPI 1942432737
  NPD
• Department of Behavioral Health & Developmental Disabilities, Ga

  • Neurology Physician
  • Thomasville, GA
  • NPI 1174942684
  NPD
• Uhs of Anchor L.P.

  • Psychiatric Hospital
  • Atlanta, GA
  • NPI 1023095429
  NPD
• Alameda County

  • Community/Behavioral Health Agency
  • Hayward, CA
  • NPI 1710252978
  NPD
• County of Alameda

  • Community/Behavioral Health Agency
  • Alameda, CA
  • NPI 1548392145
  NPD (past)

The complete NPPES record for this NPI in the NPI Registry API format.

{
    "created_epoch": "1149638400000",
    "enumeration_type": "NPI-1",
    "last_updated_epoch": "1780876800000",
    "number": "1043250079",
    "addresses": [
        {
            "country_code": "US",
            "country_name": "United States",
            "address_purpose": "MAILING",
            "address_type": "DOM",
            "address_1": "5325 BRODER BLVD",
            "city": "DUBLIN",
            "state": "CA",
            "postal_code": "945683309"
        },
        {
            "country_code": "US",
            "country_name": "United States",
            "address_purpose": "LOCATION",
            "address_type": "DOM",
            "address_1": "223 MEDICAL CENTER DR",
            "city": "RIVERDALE",
            "state": "GA",
            "postal_code": "302742640",
            "telephone_number": "770-991-8500"
        }
    ],
    "practiceLocations": [],
    "basic": {
        "last_name": "O'BRIEN",
        "first_name": "DENNIS",
        "middle_name": "ARTHUR",
        "name_prefix": "Dr.",
        "credential": "M.D.",
        "sole_proprietor": "YES",
        "sex": "M",
        "enumeration_date": "2006-06-07",
        "last_updated": "2026-06-08",
        "certification_date": "2026-06-08",
        "status": "A"
    },
    "taxonomies": [
        {
            "code": "2084P0800X",
            "taxonomy_group": "",
            "desc": "Psychiatry & Neurology, Psychiatry",
            "state": "CA",
            "license": "C161834",
            "primary": true
        },
        {
            "code": "2084P0800X",
            "taxonomy_group": "",
            "desc": "Psychiatry & Neurology, Psychiatry",
            "state": "GA",
            "license": "025893",
            "primary": false
        }
    ],
    "identifiers": [
        {
            "code": "05",
            "desc": "MEDICAID",
            "issuer": null,
            "identifier": "000483348A",
            "state": "GA"
        }
    ],
    "endpoints": [],
    "other_names": []
}

• Maria Anjanette Costales Nunez, PT
• Nurse Management Services of Georgia, Inc.
• Nursing by Faith
• Assumpta Uzomachi Nwagwu, PMHNP
• Chukwudi Christian Nwawka, MD
• Joshua Olufisayo Odeyemi, MBBS
• Lilian Omo Odion-Omonhimin, MD
• Chioma J Offodile
• Henry Ofori
• Michael Ofori, M.D

• Psychiatry Physician in Riverdale, GA
• Providers in Riverdale, GA by specialty
• Psychiatry Physician in Georgia

• NPPES NPI Registry (CMS): identity, addresses, specialties, licenses, identifiers and endpoints. Last updated by the provider on Jun 8, 2026; self-reported and not verified by CMS. Specialty names from the NUCC taxonomy.
• Medicare enrollment (CMS PECOS): enrollments, PAC IDs and benefit reassignments; Order and Referring.
• National Provider Directory (CMS): practice roles, locations, licenses, networks and endpoints.

Verify at the official NPI Registry.