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

Dr. Guy A Weiss, MD

Individual provider Student in an Organized Health Care Education/Training Program · NPI 1598084030

Dr. Guy A Weiss, MD practises Gastroenterology in Buffalo, New York. Qualified in 2010, 16 years ago. Practices with The Regents of the University of California, a 1,414-clinician group, accepts Medicare assignment and offers telehealth. Licensed in California.

Years since qualifying
16
Licensed in
CA
In the registry since
2010
Specialties on file
2
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

Student / training record This NPI belongs to someone enrolled in a health care training programme. It carries no licence and no practice of its own, so no address or phone number is published for it.

Buffalo, NY

No coordinates on file. Search this address in Google Maps

Specialties & licences

Gastroenterology Physician (primary) Taxonomy 207RG0100X · Licence A125480 (CA)
Student in an Organized Health Care Education/Training Program Taxonomy 390200000X

Record details

NPI number1598084030
Entity typeIndividual (Type 1)
GenderMale
Credentials MD
Sole proprietorNo
NPI enumeratedMay 24, 2010
Last updated in NPPESAugust 3, 2020
Certification dateAugust 3, 2020

Medicare enrollment

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

Medicare specialtyGASTROENTEROLOGY
Also practisesINTERNAL MEDICINE
Medical schoolOTHER
Graduated 2010 (16 years in practice)
Group practice The Regents Of The University Of California — 1414 clinicians
Accepts Medicare assignment Yes — accepts the Medicare-approved amount
TelehealthOffers telehealth services
Practice locations9 on file with Medicare

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 103 times · 77th percentile
Colonoscopy 55 times · 66th 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 patients407
Services billed 966 a service is one billed item, such as a visit, a test or a procedure
Average patient age71

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 $649 14 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.

Colleagues at The Regents of the University of California

Clinicians the CMS Doctors & Clinicians file lists under the same group practice. CMS counts 1414 clinicians in the practice; 12 are shown here.

Other providers in Buffalo