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Dr. John Karl Holzinger, DMD

Dr. John Karl Holzinger is a Dentist provider (Dentist) practicing in Middletown, CT, registered in the NPPES registry with NPI 1508976374 since 2006. The credential DMD stands for Doctor of Medicine in Dentistry. Practices at Hoff Consulting LLC (listed at the same practice address in NPPES).

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NPI 1508976374
Entity type Individual (Type 1)
Name Dr. John Karl Holzinger
Credential DMD
Sex Male
Practice address 770 SAYBROOK RD, Middletown, CT, 06457
Phone 8603478457
Fax 8603474393
Enumeration date 2006-08-30
Last updated in NPPES 2007-07-08

Taxonomy & licenses

Taxonomy code Specialty Primary License State
122300000X Dentist Primary 05923 CT

DMD — Doctor of Medicine in Dentistry: A licensed dentist; DMD and DDS are equivalent dental degrees. About the DMD credential

Copy-ready billing details
Provider: John Holzinger, DMD
NPI: 1508976374
Taxonomy: 122300000X (Dentist)
Address: 770 SAYBROOK RD, Middletown, CT, 06457

Other providers at this practice address

NPI Name Type Specialty Location
1245213487 Candice Weigle-Spier Individual Psychologist Middletown, CT
1346225273 Karen Gresham Individual Marriage & Family Therapist Middletown, CT
1154307668 Eileen Shekosky Individual Clinical Social Worker Middletown, CT
1235190547 Yetta Lautenschlager Individual Clinical Social Worker Middletown, CT
1669494928 Russell Harrington Individual Clinical Social Worker Middletown, CT
1790890770 Deena Robbins Individual Clinical Psychologist Middletown, CT
1518165232 Lisa Karabelnik Individual Child & Adolescent Psychiatry Physician Middletown, CT
1114101706 Robert Reynolds Individual Clinical Psychologist Middletown, CT

Verify this record

Cross-check NPI 1508976374 against the authoritative CMS record: view Dr. John Karl Holzinger on the official NPPES registry .

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 or validate an NPI number.

Frequently asked questions

What specialty is John Holzinger?
John Holzinger is registered in NPPES with the primary taxonomy of Dentist. The taxonomy code describes the provider's classification and area of specialization for claims and credentialing.
Is this the official NPI registry?
No. NPI Portal is a private site built on public CMS NPPES data. The official registry is npiregistry.cms.hhs.gov, operated by CMS.

Source: CMS NPPES (public data). Snapshot 2026-07-11. Provider record last updated 2007-07-08.