William Oh, M.D.
NPI 1598100323ActiveIndividual· Colon & Rectal Surgery· Irvine, CA
Colon & Rectal Surgery (M.D.) with Hoag Clinic, practicing in Irvine, California. 111 Medicare patients in 2024, $61,019 paid; nearly all of their 111 Part D prescriptions were generic (92%). Astrazeneca Pharmaceuticals LP was the largest of 4 companies reporting payments in 2025, $242.49 in all, mostly food and beverage. Lists Hoag Memorial Hospital Presbyterian as a hospital affiliation.
Overview
| NPI | 1598100323 |
|---|---|
| Status | Active |
| Entity type | Individual |
| Credential | M.D. |
| Sole proprietor | No |
| NPI issued | May 7, 2013 |
| Last updated in NPPES | May 7, 2026 |
| Certified by provider | May 7, 2026 |
Specialties and licenses
| Taxonomy | Code | License | State |
|---|---|---|---|
| Colon & Rectal Surgery Primary | 208C00000X | A136780 | CA |
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 - Colorectal Surgery (Proctology) (CA); Practitioner - General Surgery (WA) |
|---|---|
| Accepts assignment | Yes (participating) |
Medicare services in 2024
| Medicare patients | 111 |
|---|---|
| Services billed | 274 across 50 procedure codes |
| Paid by Medicare | $61,019 |
Part D prescriptions in 2024
| Prescriptions (claims) | 111 · 111 30-day fills |
|---|---|
| Patients | 45 |
| Total drug cost | $4,074 |
| Generic share | 92% of claims |
Education and affiliations
| Graduation year | 2013 |
|---|---|
| Medicare specialty | Colorectal Surgery (Proctology) |
Medical group
- Hoag ClinicNewport Beach, CA · 460 clinicians
Hospital affiliation
- Hoag Memorial Hospital PresbyterianNewport Beach, CA
Other facilities
- Hoag Home HealthHome health agency · Newport Beach, CA
Industry payments (Open Payments)
- 2025$242.49 · 5 payments from 4 companies
- 2024$133.51 · 5 payments from 4 companies
Top paying companies in 2025
| Company | Amount | Payments |
|---|---|---|
| Astrazeneca Pharmaceuticals LP | $146.35 | 1 |
| Janssen Biotech, Inc. | $39.88 | 2 |
| Lilly USA, LLC | $28.37 | 1 |
| Genzyme Corporation | $27.89 | 1 |
What the 2025 payments were for
- Food and Beverage$242.49 · 5 payments
Receiving payments does not imply wrongdoing. What Open Payments covers ·original records
Other colorectal surgeons in Irvine
- 1083829956
- 1366760514
- 1750762001
- 1942216940
- 1093006223
- 1124322052
- 1811187560
- 1093056780