Andrew James Overhiser, M.D.
NPI 1679789549ActiveIndividual· Internal Medicine, Gastroenterology· Flagstaff, AZ
Internal Medicine, Gastroenterology (M.D.) in Flagstaff, Arizona, trained at Indiana University School of Medicine (class of 2004). Their prescriptions cost Medicare Part D more than their services did: $118,323 for 826 claims, against $63,706 paid for services in 2024. Genzyme Corporation was the largest of 12 companies reporting payments in 2025, $532.75 in all, mostly food and beverage.
Overview
| NPI | 1679789549 |
|---|---|
| Status | Active |
| Entity type | Individual |
| Credential | M.D. |
| Sole proprietor | No |
| NPI issued | May 15, 2007 |
| Last updated in NPPES | Dec 12, 2024 |
| Certified by provider | Dec 12, 2024 |
Specialties and licenses
| Taxonomy | Code | License | State |
|---|---|---|---|
| Internal Medicine, Gastroenterology Primary | 207RG0100X | 42636 | AZ |
Exclusion screening
| List | Result | Details |
|---|---|---|
| HHS-OIG LEIE · Nov 10, 2026 | No match | Checked by NPI and by name + state |
| North Carolina Medicaid · Nov 11, 2026 | No match | — |
| New York OMIG · Nov 11, 2026 | No match | — |
| Ohio Medicaid · Nov 11, 2026 | No match | — |
| Pennsylvania Medicheck · Nov 11, 2026 | No match | — |
| Washington HCA · Nov 11, 2026 | No match | — |
Official OIG search · How matching works ·Bulk check a roster
Medicare
| Enrollment (PECOS) | Enrolled Practitioner - Gastroenterology (AZ) |
|---|---|
| Accepts assignment | Yes (participating) |
Medicare services in 2024
| Medicare patients | 347 |
|---|---|
| Services billed | 531 across 31 procedure codes |
| Paid by Medicare | $63,706 |
Part D prescriptions in 2024
| Prescriptions (claims) | 826 · 1,101 30-day fills |
|---|---|
| Patients | 493 |
| Total drug cost | $118,323 |
| Generic share | 83% of claims |
Education and affiliations
| Medical school | Indiana University School of Medicine |
|---|---|
| Graduation year | 2004 |
| Medicare specialty | Gastroenterology |
| Telehealth | Offers telehealth |
Medical group
- Northern Arizona Healthcare CorporationFlagstaff, AZ · 385 clinicians
Hospital affiliations
- Flagstaff Medical CenterFlagstaff, AZ
- Verde Valley Medical CenterCottonwood, AZ
Industry payments (Open Payments)
- 2025$532.75 · 22 payments from 12 companies
- 2024$420.98 · 16 payments from 9 companies
Top paying companies in 2025
| Company | Amount | Payments |
|---|---|---|
| Genzyme Corporation | $71.28 | 3 |
| Madrigal Pharmaceuticals | $69.88 | 2 |
| Merit Medical Systems Inc | $68.91 | 1 |
| Abbvie Inc. | $51.61 | 3 |
| Lilly USA, LLC | $45.51 | 2 |
What the 2025 payments were for
- Food and Beverage$532.75 · 22 payments
Receiving payments does not imply wrongdoing. What Open Payments covers ·original records
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All Internal Medicine, Gastroenterology providers in Arizona →