Provider records sourced from NPPES (CMS National Plan & Provider Enumeration System). Data current as of October 4, 2026.
NPIDirectory

Peter Edwin Darwin, MD

Individual provider Gastroenterology Physician · NPI 1649231481

Peter Edwin Darwin, MD practises Gastroenterology in Baltimore, Maryland. Graduated from University of Maryland School of Medicine in 1990, 36 years ago. Practices with Kaiser Foundation Health Plan of the Mid Atlantic States, Inc, a 1,934-clinician group and accepts Medicare assignment. Licensed in Maryland.

Years since qualifying
36
Trained at
University of Maryland School of Medicine
Licensed in
MD
In the registry since
2006
What do these letters mean?
MD — Doctor of Medicine
A physician who completed allopathic medical school.

See every abbreviation used in this directory →

Claim this listing Report a problem Suggest an edit

Practice location Address checks out

22 S Greene St
Baltimore, MD 21201-1544 Not confirmed with CMS for 15 years — call before visiting
Phone: (410) 328-8729
Fax: (410) 328-8315
Show map & directions

Directions in Google Maps · Apple Maps · OpenStreetMap

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

Specialties & licences

Gastroenterology Physician (primary) Taxonomy 207RG0100X · Licence D42781 (MD)

Record details

NPI number1649231481
Entity typeIndividual (Type 1)
GenderMale
Credentials MD
Sole proprietorNo
NPI enumeratedMarch 31, 2006
Last updated in NPPESDecember 27, 2010

Medicare enrollment

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

Medicare specialtyGASTROENTEROLOGY
Also practisesINTERNAL MEDICINE
Medical schoolUNIVERSITY OF MARYLAND SCHOOL OF MEDICINE
Graduated 1990 (36 years in practice)
Group practice Kaiser Foundation Health Plan Of The Mid Atlantic States, Inc — 1934 clinicians
Accepts Medicare assignment Yes — accepts the Medicare-approved amount

Procedures

From CMS Care Compare, which counts the procedures a clinician billed to Original Medicare and Medicare Advantage over a recent 12-month period. CMS reports a fixed list of common procedures, so this is not everything the clinician does. Counts of 10 or fewer are given as a range, because CMS withholds small numbers.

Upper gastrointestinal (GI) endoscopy for acid reflux 88 times · 74th percentile
Colonoscopy 19 times · 47th percentile

The percentile compares how often this clinician performed the procedure with other clinicians who performed it, as CMS calculates it. It measures volume, not outcomes or skill.

Medicare patients and services, 2024

From the CMS Medicare Physician & Other Practitioners file for calendar year 2024. It counts Original Medicare patients only, so a practice that mostly sees Medicare Advantage or privately insured patients looks smaller here than it is.

Medicare patients361
Services billed 663 a service is one billed item, such as a visit, a test or a procedure
Average patient age73

Dollar amounts are not shown. What Medicare pays a practice is gross billings, before staff, premises and tax and including the cost of any drugs it administers, so it is not what a clinician earns.

Payments from drug and device companies, 2025

Drug and device makers are required by federal law (the Physician Payments Sunshine Act) to report what they pay or give to clinicians, and CMS publishes the reports as Open Payments. This is the 2025 program year. A report is a record of a payment, not an allegation of anything, and many are small items such as meals. Only general payments are listed here; research payments and ownership or investment interests are reported separately by CMS and are not shown.

Food and Beverage $59 3 payments · a meal or drink at a meeting or visit, not a fee

Each amount is the sum of what companies reported for that kind of payment in 2025, rounded to the dollar. Not all of it is income to the clinician: a meal is not a fee, a charitable contribution goes to a charity, and a royalty or an acquisition payment is not a salary.

Check a report, or dispute one, at the source in CMS’s own tool, Open Payments. Corrections go through CMS’s dispute process. This site removes a home address on request and asks for no proof, because that is privacy; it will not remove an accurate payment report on request, because that is a statutory public disclosure.

Colleagues at Kaiser Foundation Health Plan of the Mid Atlantic States, Inc

Clinicians the CMS Doctors & Clinicians file lists under the same group practice. CMS counts 1934 clinicians in the practice; 12 are shown here.

Other providers in Baltimore