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

Dr. William Colin Gallahan, MD

Individual provider Internal Medicine Physician · NPI 1508040213

Dr. William Colin Gallahan, MD practises Gastroenterology in Winston Salem, North Carolina. Graduated from University of Virginia School of Medicine in 2004, 22 years ago. Practices with Richmond Gastroenterology Associates, Inc, a 39-clinician group, accepts Medicare assignment and offers telehealth. Licensed in North Carolina.

Years since qualifying
22
Trained at
University of Virginia School of Medicine
Licensed in
NC
In the registry since
2007
What do these letters mean?
MD — Doctor of Medicine
A physician who completed allopathic medical school.

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Practice location Partly verified

Some contact details are missing from the federal record.

Wake Forest University Health Sciences Medical Center Blvd
Winston Salem, NC 27157-0001 Not confirmed with CMS for 16 years — call before visiting
Phone: (336) 716-2255
Show map & directions

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

Specialties & licences

Internal Medicine Physician (primary) Taxonomy 207R00000X · Licence 2010-00678 (NC)

Record details

NPI number1508040213
Entity typeIndividual (Type 1)
GenderMale
Credentials MD
Sole proprietorNo
NPI enumeratedDecember 18, 2007
Last updated in NPPESMay 5, 2010

Medicare enrollment

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

Medicare specialtyGASTROENTEROLOGY
Also practisesINTERNAL MEDICINE
Medical schoolUNIVERSITY OF VIRGINIA SCHOOL OF MEDICINE
Graduated 2004 (22 years in practice)
Group practice Richmond Gastroenterology Associates, Inc. — 39 clinicians
Accepts Medicare assignment Yes — accepts the Medicare-approved amount
TelehealthOffers telehealth services

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 173 times · 88th percentile
Colonoscopy 119 times · 83rd 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 patients869
Services billed 1,381 a service is one billed item, such as a visit, a test or a procedure
Average patient age75

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 $2,045 102 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.

Practises at

Facilities the CMS Facility Affiliation file lists for this clinician. Those with a page here are linked.

Also affiliated with 1 inpatient rehabilitation facility, which CMS identifies by certification number only.

Colleagues at Richmond Gastroenterology Associates, Inc

Clinicians the CMS Doctors & Clinicians file lists under the same group practice. CMS counts 39 clinicians in the practice; 12 are shown here.

Other providers in Winston Salem