NPI Portal NPI Lookup & Verification

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

Mr. Gregory F Guenther, R.PH,.

Pharmacist in Chesterfield, MO · enumerated 2013.

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

National Provider Identifier

1184063661

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Registry record

Entity type Individual (Type 1)
Name Mr. Gregory F Guenther
Credential R.PH,.
Sex Male
Practice address Chesterfield, MO, 63017
Phone (636) 812-1472
Enumeration date Jun 18, 2013
Last updated in NPPES Jun 18, 2013

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

Taxonomy & licenses

183500000X Pharmacist Pharmacy Service Providers · License 040991 (MO) Primary
RPH · Registered Pharmacist: A licensed pharmacist registered with a state board of pharmacy. About the RPH credential

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.

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Frequently asked questions

Is NPI 1184063661 active?
Yes, as of the latest NPPES snapshot, NPI 1184063661 is active (record last updated 2013-06-18).
How do I verify Gregory Guenther's NPI record?
Cross-check NPI 1184063661 against the official CMS registry at npiregistry.cms.hhs.gov. This page mirrors the same public NPPES data with a monthly snapshot.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2013-06-18.