Leonard I Leven, M.D.

Primary specialty

Child & Adolescent Psychiatry PhysicianTaxonomy code 2084P0804X

License

167310 Issued in NY

Practice address

3 W End Ave
Old Greenwich, CT 06870-1640

Phone

(203) 637-1486

Fax

(203) 637-1486

NPI assigned

Jul 28, 2005

Last updated

Jul 13, 2026By the provider in NPPES

Sex

Male

Sole proprietor

No

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

Specialties & licenses 4

Addresses

Medicare fee-for-service enrollment

Not listed in the public Medicare enrollment file

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.

Opted out of Medicare

Yes, effective Jul 1, 2014 through Jul 1, 2028

Medicare enrollment (NPD)

Enrolled

Credentials

Doctor of Medicine

State licenses

Practice roles

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

• Revision Studio LLC Therapy and Counseling Services

  • Clinical Social Worker
  • Old Greenwich, CT
  • NPI 1841639556
  NPD (past)

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

{
    "created_epoch": "1122508800000",
    "enumeration_type": "NPI-1",
    "last_updated_epoch": "1783900800000",
    "number": "1821098245",
    "addresses": [
        {
            "country_code": "US",
            "country_name": "United States",
            "address_purpose": "MAILING",
            "address_type": "DOM",
            "address_1": "3 BAYBERRY RD",
            "city": "ELMSFORD",
            "state": "NY",
            "postal_code": "105231701",
            "telephone_number": "914-347-4510",
            "fax_number": "914-347-5020"
        },
        {
            "country_code": "US",
            "country_name": "United States",
            "address_purpose": "LOCATION",
            "address_type": "DOM",
            "address_1": "3 W END AVE",
            "city": "OLD GREENWICH",
            "state": "CT",
            "postal_code": "068701640",
            "telephone_number": "203-637-1486",
            "fax_number": "203-637-1486"
        }
    ],
    "practiceLocations": [],
    "basic": {
        "last_name": "LEVEN",
        "first_name": "LEONARD",
        "middle_name": "I",
        "name_prefix": "Dr.",
        "credential": "M.D.",
        "sole_proprietor": "NO",
        "sex": "M",
        "enumeration_date": "2005-07-28",
        "last_updated": "2026-07-13",
        "status": "A"
    },
    "taxonomies": [
        {
            "code": "2084P0800X",
            "taxonomy_group": "",
            "desc": "Psychiatry & Neurology, Psychiatry",
            "state": "CT",
            "license": "026744",
            "primary": false
        },
        {
            "code": "2084P0800X",
            "taxonomy_group": "",
            "desc": "Psychiatry & Neurology, Psychiatry",
            "state": "NY",
            "license": "167310",
            "primary": false
        },
        {
            "code": "2084P0804X",
            "taxonomy_group": "",
            "desc": "Psychiatry & Neurology, Child & Adolescent Psychiatry",
            "state": "CT",
            "license": "026744",
            "primary": false
        },
        {
            "code": "2084P0804X",
            "taxonomy_group": "",
            "desc": "Psychiatry & Neurology, Child & Adolescent Psychiatry",
            "state": "NY",
            "license": "167310",
            "primary": true
        }
    ],
    "identifiers": [],
    "endpoints": [],
    "other_names": []
}

• Inna Lazar, OD
• Sarah Kate Leahey
• Samantha Leichtner
• Allison Lepontois
• Madeleine Lerose
• Eileen Li, PT, DPT, L.AC
• Vladimir Lialine
• Courtney Liebowitz, PA-C
• Johnny Lin, PHARMD
• Alison Goldstein Lomazow, M.S., CCC-SLP

• Child & Adolescent Psychiatry Physician in Old Greenwich, CT
• Providers in Old Greenwich, CT by specialty
• Child & Adolescent Psychiatry Physician in Connecticut

• NPPES NPI Registry (CMS): identity, addresses, specialties, licenses, identifiers and endpoints. Last updated by the provider on Jul 13, 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; Opt Out Affidavits.
• National Provider Directory (CMS): practice roles, locations, licenses, networks and endpoints.

Verify at the official NPI Registry.