Matthew A Stack, PAC

Individual provider Psychologist · NPI 1033108667

Matthew A Stack, PAC is a Physician Assistant in Ithaca, Michigan. Qualified in 2002, 24 years ago. Practices with Genesee Health System, a 37-clinician group, works from 2 locations and accepts Medicare assignment. Licensed in Arizona and Michigan.

Years since qualifying: 24
Licensed in: AZ, MI
In the registry since: 2005
Specialties on file: 4

What do these letters mean?

PAC — Physician Assistant, Certified: A physician assistant holding current national certification; usually written PA-C.

See every abbreviation used in this directory →

Claim this listing Report a problem Suggest an edit

Practice location Address checks out

121 N Pine River St
Ithaca, MI 48847-1039
Phone: (989) 287-0662

Show map & directions

Directions in Google Maps · Apple Maps · OpenStreetMap

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

Additional practice locations (1)

1040 W Bristol Rd, Flint, MI 48507-5516 — (810) 257-3705

Specialties & licences

Physician Assistant (primary)	Taxonomy 363A00000X · Licence 5601003961 (MI)
Psychologist	Taxonomy 103T00000X · Licence 6301007939 (MI)
Medical Physician Assistant	Taxonomy 363AM0700X
Physician Assistant	Taxonomy 363A00000X · Licence 2782 (AZ)

Record details

NPI number	1033108667
Entity type	Individual (Type 1)
Gender	Male
Credentials	PAC
Sole proprietor	No
NPI enumerated	October 17, 2005
Last updated in NPPES	February 5, 2026
Certification date	February 5, 2026

Medicare enrollment

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

Medicare specialty	PHYSICIAN ASSISTANT
Medical school	OTHER
Graduated	2002 (24 years in practice)
Group practice	Genesee Health System — 37 clinicians
Accepts Medicare assignment	Yes — accepts the Medicare-approved amount
Practice locations	3 on file with Medicare

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	$68 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 Genesee Health System

Clinicians the CMS Doctors & Clinicians file lists under the same group practice. CMS counts 37 clinicians in the practice; 12 are shown here.

Kevin Anthony Allen, MA, LLPC Counselor · Flint, MI
Kelsey Ellis, OTR Occupational Therapist · Flint, MI
Sarah Ann Graybill, PA-C Physician Assistant · Flint, MI
Melissa Healey, LMSW Clinical Social Worker · Flint, MI
Mr. Robert Milton Hughes, PA-C Physician Assistant · Flint, MI
Mr. Joseph Karanja, FNP General Practice Registered Nurse · Flint, MI
Jon Russell Krueger, PMHNP Psychiatric/Mental Health Nurse Practitioner · Flint, MI
Dr. Sarah Alia Matto, MD Psychiatry Physician · Flint, MI
Michelle Lee McKown, MOTRL Occupational Therapist · Flint, MI
Karen Palomares, LMSW Clinical Social Worker · Flint, MI
Dr. Son H Phung, MD Internal Medicine Physician · Flint, MI
Dr. Opal Erika Randolph, DO Psychiatry Physician · Flint, MI