Provider records sourced from NPPES (CMS National Plan & Provider Enumeration System). Data current as of August 10, 2026.

Dr. Gretchen Elizabeth Twork, MD

Individual provider Internal Medicine Physician · NPI 1588759872

Dr. Gretchen Elizabeth Twork, MD is an Internal Medicine in Lebanon, New Hampshire. Qualified in 2002, 24 years ago. Practices with Dartmouth-Hitchcock Clinic, a 1,430-clinician group and accepts Medicare assignment. Licensed in New Hampshire.

Years since qualifying
24
Licensed in
NH
In the registry since
2006
What do these letters mean?
MD — Doctor of Medicine
A physician who completed allopathic medical school.

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Practice location Address checks out

1 Medical Center Dr
Lebanon, NH 03756-1000
Phone: (603) 650-8380
Fax: (603) 640-1228
Show map & directions

Pin is approximate — placed at the ZIP-code centre, not the exact door.

Specialties & licences

Internal Medicine Physician (primary) Taxonomy 207R00000X · Licence 12768 (NH)

Record details

NPI number1588759872
Entity typeIndividual (Type 1)
GenderFemale
Credentials MD
Sole proprietorYes
NPI enumeratedOctober 4, 2006
Last updated in NPPESDecember 16, 2025
Certification dateDecember 16, 2025

Medicare enrollment

From the CMS Doctors & Clinicians file — this clinician is enrolled in Medicare.

Medicare specialtyINTERNAL MEDICINE
Medical schoolOTHER
Graduated 2002 (24 years in practice)
Group practice Dartmouth-Hitchcock Clinic — 1430 clinicians
Accepts Medicare assignment Yes — accepts the Medicare-approved amount
Practice locations3 on file with Medicare

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