Guidestar Eldercare - Il SC

Primary specialty

Internal Medicine PhysicianTaxonomy code 207R00000X

Legal business name

GUIDESTAR ELDERCARE - IL SC

Doing business as

Vanguard Eldercare - Illinois, S.C.

Practice address

1821 Walden Office SQ Ste 400
Schaumburg, IL 60173-4273

Phone

(574) 546-1900

Fax

(574) 546-1999

NPI assigned

Nov 6, 2019

Last updated

Apr 24, 2025By the provider in NPPES

Organization subpart

No

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

Authorized official

Name

Mr. Steven Posar, MDNPI 1154308575

Title

Ceo

Phone

(574) 546-1900

Specialties & licenses 9

Addresses

Other names 1

• Vanguard Eldercare - Illinois, S.C. Doing business as

Practitioners 1

Individual providers connected to this organization through Medicare benefit reassignment, Care Compare group membership or National Provider Directory roles, and the practitioner matching its NPPES authorized official.

• Steven L Posar, MD

  • Internal Medicine Physician
  • Crown Point, IN
  • NPI 1154308575
  Authorized official Same address or phone

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

{
    "created_epoch": "1572998400000",
    "enumeration_type": "NPI-2",
    "last_updated_epoch": "1745452800000",
    "number": "1417591074",
    "addresses": [
        {
            "country_code": "US",
            "country_name": "United States",
            "address_purpose": "MAILING",
            "address_type": "DOM",
            "address_1": "PO BOX 10633",
            "city": "FORT WAYNE",
            "state": "IN",
            "postal_code": "468530633",
            "telephone_number": "574-546-1900",
            "fax_number": "574-546-1999"
        },
        {
            "country_code": "US",
            "country_name": "United States",
            "address_purpose": "LOCATION",
            "address_type": "DOM",
            "address_1": "1821 WALDEN OFFICE SQ STE 400",
            "city": "SCHAUMBURG",
            "state": "IL",
            "postal_code": "601734273",
            "telephone_number": "574-546-1900",
            "fax_number": "574-546-1999"
        }
    ],
    "practiceLocations": [
        {
            "address_1": "1440 N Lake Shore Dr Apt 12D",
            "address_purpose": "LOCATION",
            "city": "Chicago",
            "state": "IL",
            "postal_code": "606105909",
            "country_code": "US",
            "telephone_number": "574-546-1900",
            "fax_number": "574-546-1999",
            "country_name": "United States",
            "address_type": "DOM"
        }
    ],
    "basic": {
        "organization_name": "GUIDESTAR ELDERCARE - IL SC",
        "organizational_subpart": "NO",
        "enumeration_date": "2019-11-06",
        "last_updated": "2025-04-24",
        "certification_date": "2025-04-16",
        "status": "A",
        "authorized_official_last_name": "POSAR",
        "authorized_official_first_name": "STEVEN",
        "authorized_official_title_or_position": "CEO",
        "authorized_official_telephone_number": "574-546-1900",
        "authorized_official_name_prefix": "Mr.",
        "authorized_official_credential": "MD"
    },
    "taxonomies": [
        {
            "code": "101YM0800X",
            "taxonomy_group": "",
            "desc": "Counselor, Mental Health",
            "state": "NU",
            "license": null,
            "primary": false
        },
        {
            "code": "103TC0700X",
            "taxonomy_group": "",
            "desc": "Psychologist, Clinical",
            "state": "NU",
            "license": null,
            "primary": false
        },
        {
            "code": "1041C0700X",
            "taxonomy_group": "",
            "desc": "Social Worker, Clinical",
            "state": "NU",
            "license": null,
            "primary": false
        },
        {
            "code": "207R00000X",
            "taxonomy_group": "",
            "desc": "Internal Medicine",
            "state": "NU",
            "license": null,
            "primary": true
        },
        {
            "code": "2084N0400X",
            "taxonomy_group": "",
            "desc": "Psychiatry & Neurology, Neurology",
            "state": "NU",
            "license": null,
            "primary": false
        },
        {
            "code": "363L00000X",
            "taxonomy_group": "",
            "desc": "Nurse Practitioner",
            "state": "NU",
            "license": null,
            "primary": false
        },
        {
            "code": "363LF0000X",
            "taxonomy_group": "",
            "desc": "Nurse Practitioner, Family",
            "state": "NU",
            "license": null,
            "primary": false
        },
        {
            "code": "363LG0600X",
            "taxonomy_group": "",
            "desc": "Nurse Practitioner, Gerontology",
            "state": "NU",
            "license": null,
            "primary": false
        },
        {
            "code": "363LP0808X",
            "taxonomy_group": "",
            "desc": "Nurse Practitioner, Psychiatric/Mental Health",
            "state": "NU",
            "license": null,
            "primary": false
        }
    ],
    "identifiers": [],
    "endpoints": [],
    "other_names": [
        {
            "organization_name": "Vanguard Eldercare - Illinois, S.C.",
            "code": "3",
            "type": "Doing Business As"
        }
    ]
}

• Ronald Grossmayer, RPH
• Grace Grubb, RBT
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• Tianna Guerra
• Britt E Guerrero, ARNP
• Paige Gulbrandsen, MA, BCBA
• Patrick Gunderson, PH.D.
• Lynda Gundling, OTR
• Earl Edward Gunther Jr., P.T.
• Vipan Kumar Gupta, MD

• Internal Medicine Physician in Schaumburg, IL
• Providers in Schaumburg, IL by specialty
• Internal Medicine Physician in Illinois

• NPPES NPI Registry (CMS): identity, addresses, specialties, licenses, identifiers and endpoints. Last updated by the provider on Apr 24, 2025; self-reported and not verified by CMS. Specialty names from the NUCC taxonomy.
• National Provider Directory (CMS): practice roles, locations, licenses, networks and endpoints.

Verify at the official NPI Registry.