M. Mazen Jamal, M.D., M.P.H.
NPI 1003916727ActiveIndividual· Internal Medicine, Gastroenterology· Corona, CA
Internal Medicine, Gastroenterology (M.D., M.P.H.) with Mj Medical Group,inc., practicing in Corona, California. In 2024 Medicare paid $211,139 for 810 patients, and Part D covered 540 of their prescriptions, 88% of them generic. Abbvie Inc. was the largest of 12 companies reporting payments in 2025, $959.21 in all, mostly food and beverage. Lists Corona Regional Medical Center as a hospital affiliation.
Overview
| NPI | 1003916727 |
|---|---|
| Status | Active |
| Entity type | Individual |
| Credential | M.D., M.P.H. |
| Sole proprietor | No |
| NPI issued | Sep 23, 2006 |
| Last updated in NPPES | Jun 24, 2021 |
| Certified by provider | Jun 24, 2021 |
Specialties and licenses
| Taxonomy | Code | License | State |
|---|---|---|---|
| Internal Medicine, Gastroenterology Primary | 207RG0100X | A46078 | CA |
| Internal Medicine, Gastroenterology | 207RG0100X | 12734 | NV |
Exclusion screening
| List | Result | Details |
|---|---|---|
| HHS-OIG LEIE · Oct 9, 2026 | No match | Checked by NPI and by name + state |
| North Carolina Medicaid · Nov 4, 2026 | No match | — |
| New York OMIG · Nov 4, 2026 | No match | — |
| Ohio Medicaid · Nov 4, 2026 | No match | — |
| Pennsylvania Medicheck · Nov 4, 2026 | No match | — |
| Washington HCA · Nov 4, 2026 | No match | — |
Official OIG search · How matching works ·Bulk check a roster
Medicare
| Enrollment (PECOS) | Enrolled Practitioner - Gastroenterology (CA) |
|---|---|
| Accepts assignment | Yes (participating) |
Medicare services in 2024
| Medicare patients | 810 |
|---|---|
| Services billed | 2,013 across 41 procedure codes |
| Paid by Medicare | $211,139 |
Part D prescriptions in 2024
| Prescriptions (claims) | 540 · 736 30-day fills |
|---|---|
| Patients | 301 |
| Total drug cost | $69,271 |
| Generic share | 88% of claims |
Education and affiliations
| Graduation year | 1981 |
|---|---|
| Medicare specialty | Gastroenterology |
| Telehealth | Offers telehealth |
Medical group
- Mj Medical Group,inc.Foothill Ranch, CA · 2 clinicians
Hospital affiliation
- Corona Regional Medical CenterCorona, CA
Industry payments (Open Payments)
- 2025$959.21 · 42 payments from 12 companies
- 2024$273.48 · 11 payments from 8 companies
Top paying companies in 2025
| Company | Amount | Payments |
|---|---|---|
| Abbvie Inc. | $248.88 | 15 |
| Janssen Biotech, Inc. | $205.63 | 8 |
| Medtronic, Inc. | $109.30 | 1 |
| Lilly USA, LLC | $99.37 | 3 |
| Madrigal Pharmaceuticals | $64.85 | 2 |
What the 2025 payments were for
- Food and Beverage$860.21 · 41 payments
- Education$99.00 · 1 payment
Receiving payments does not imply wrongdoing. What Open Payments covers ·original records
Other Internal Medicine, Gastroenterology providers in Corona
- 1699194423
- 1871841692
- 1811316458
- 1619102837
- 1902167695
- 1417226366
All Internal Medicine, Gastroenterology providers in California →