Type 1 · Individual ✓ Active NPI ✓ Valid NPI checksum Sole proprietor

Mary Elizabeth O'Brien, LCPC

Professional Counselor in Edgewater, MD · enumerated 2008.

Data current as of Jul 13, 2026 · sourced from CMS NPPES

National Provider Identifier

1588834493

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Registry record

Entity type Individual (Type 1)

Name Mary Elizabeth O'Brien

Credential LCPC

Sex Female

Practice address Edgewater, MD, 21037

Phone (410) 303-2982

Fax (410) 956-7686

Enumeration date Mar 6, 2008

Last updated in NPPES Mar 15, 2013

Street address withheld: NPPES sole-proprietor addresses can be home addresses. See our data policy.

Taxonomy & licenses

101YP2500X Professional Counselor Behavioral Health & Social Service Providers · License LC1003 (MD) Primary

Other identifiers

Identifier	Type	State	Issuer
167750100	Medicaid	MD	-

What is an NPI number?

A National Provider Identifier (NPI) is a unique 10-digit number that CMS assigns to every U.S. healthcare provider and organization under HIPAA. Type 1 NPIs identify individual providers; Type 2 NPIs identify organizations. The NPI appears on insurance claims, prescriptions, and credentialing paperwork, and never changes, even if the provider moves or changes specialty.

Read the full guide → Validate an NPI →

Frequently asked questions

Is NPI 1588834493 active?

Yes, as of the latest NPPES snapshot, NPI 1588834493 is active (record last updated 2013-03-15).

How do I verify Mary O'Brien's NPI record?

Cross-check NPI 1588834493 against the official CMS registry at npiregistry.cms.hhs.gov. This page mirrors the same public NPPES data with a monthly snapshot.

Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2013-03-15.