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

David M McMahon, DO

Individual provider Psychiatry Physician · NPI 1457662249

David M McMahon, DO practises Psychiatry in Green Bay, Wisconsin. Graduated from Des Moines University of Osteopathic Medicine and Health Sciences in 2010, 16 years ago. Practices with Affiliated Clinical Services Inc, a 22-clinician group, accepts Medicare assignment and offers telehealth. Licensed in Wisconsin.

Years since qualifying
16
Trained at
Des Moines University of Osteopathic Medicine and Health Sciences
Licensed in
WI
In the registry since
2010
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.

See every abbreviation used in this directory →

Claim this listing Report a problem Suggest an edit

Practice location Address checks out

301 E Saint Joseph St
Green Bay, WI 54301-2241
Phone: (920) 433-3630
Fax: (920) 437-0533
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

Psychiatry Physician (primary) Taxonomy 2084P0800X · Licence 63216-21 (WI)

Record details

NPI number1457662249
Entity typeIndividual (Type 1)
GenderMale
Credentials DO
Sole proprietorNo
NPI enumeratedJune 25, 2010
Last updated in NPPESOctober 18, 2021
Certification dateOctober 18, 2021

Medicare enrollment

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

Medicare specialtyPSYCHIATRY
Medical schoolDES MOINES UNIVERSITY OF OSTEOPATHIC MEDICINE AND HEALTH SCIENCES
Graduated 2010 (16 years in practice)
Group practice Affiliated Clinical Services Inc — 22 clinicians
Accepts Medicare assignment Yes — accepts the Medicare-approved amount
TelehealthOffers telehealth services
Practice locations3 on file with Medicare

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 patients73
Services billed 474 a service is one billed item, such as a visit, a test or a procedure
Average patient age58

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 $1,869 97 payments · a meal or drink at a meeting or visit, not a fee
Education $227 3 payments · educational material or training, 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 Affiliated Clinical Services Inc

Clinicians the CMS Doctors & Clinicians file lists under the same group practice. CMS counts 22 clinicians in the practice; 12 are shown here.

Other providers in Green Bay