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

John Walker, DO

Individual provider Internal Medicine Physician · NPI 1851737811

John Walker, DO is a Gastroenterology in Portland, Maine. Qualified in 2013, 13 years ago. Practices with Mainehealth, a 2,615-clinician group and accepts Medicare assignment. Licensed in Maine.

Years since qualifying
13
Licensed in
ME
In the registry since
2013
What do these letters mean?
DO — Doctor of Osteopathic Medicine
A fully licensed physician, trained like an MD with additional musculoskeletal training. Equivalent practice rights in all 50 states.

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Practice location Address checks out

22 Bramhall St
Portland, ME 04102-3134
Phone: (207) 662-6562
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 DO2640 (ME)

Record details

NPI number1851737811
Entity typeIndividual (Type 1)
GenderMale
Credentials DO
Sole proprietorNo
NPI enumeratedMay 17, 2013
Last updated in NPPESJune 21, 2016
Mailing address300 Southborough Dr, Suite 201, South Portland, ME 04106-6914

Medicare enrollment

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

Medicare specialtyGASTROENTEROLOGY
Also practisesINTERNAL MEDICINE
Medical schoolOTHER
Graduated 2013 (13 years in practice)
Group practice Mainehealth — 2615 clinicians
Accepts Medicare assignment Yes — accepts the Medicare-approved amount
Practice locations3 on file with Medicare

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