Ennis Zaitoon, M.D.
NPI 1235307141ActiveIndividual· Internal Medicine· Corona, CA
Internal Medicine (M.D.) with Riverside Medical Clinic Inc, practicing in Corona, California. Their prescriptions cost Medicare Part D more than their services did: $552,704 for 4,293 claims, against $53,475 paid for services in 2024. Lilly USA, LLC was the largest of 4 companies reporting payments in 2025, $4,932 in all, mostly speaking and faculty fees.
Overview
| NPI | 1235307141 |
|---|---|
| Status | Active |
| Entity type | Individual |
| Credential | M.D. |
| Sole proprietor | No |
| NPI issued | Feb 13, 2008 |
| Last updated in NPPES | Sep 17, 2024 |
| Certified by provider | Sep 17, 2024 |
Specialties and licenses
| Taxonomy | Code | License | State |
|---|---|---|---|
| Internal Medicine Primary | 207R00000X | C160730 | CA |
| Internal Medicine | 207R00000X | 01067223 | IN |
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 - Internal Medicine (CA) |
|---|---|
| Accepts assignment | Yes (participating) |
Medicare services in 2024
| Medicare patients | 151 |
|---|---|
| Services billed | 723 across 41 procedure codes |
| Paid by Medicare | $53,475 |
Part D prescriptions in 2024
| Prescriptions (claims) | 4,293 · 10,122 30-day fills |
|---|---|
| Patients | 382 |
| Total drug cost | $552,704 |
| Generic share | 84% of claims |
Education and affiliations
| Graduation year | 2004 |
|---|---|
| Medicare specialty | Internal Medicine |
| Telehealth | Offers telehealth |
Medical group
- Riverside Medical Clinic IncRiverside, CA · 173 clinicians
Other facilities
- Lorian HealthHome health agency · Riverside, CA
Industry payments (Open Payments)
- 2025$4,932 · 13 payments from 4 companies
- 2024$227.28 · 11 payments from 7 companies
Top paying companies in 2025
| Company | Amount | Payments |
|---|---|---|
| Lilly USA, LLC | $4,688 | 6 |
| Novo Nordisk Inc | $201.54 | 5 |
| Edwards Lifesciences Corporation | $22.89 | 1 |
| Exact Sciences Corporation | $19.33 | 1 |
What the 2025 payments were for
- Compensation for services other than consulting, including serving as faculty or as a speaker at a venue other than a continuing education program$4,550 · 4 payments
- Food and Beverage$368.75 · 8 payments
- Travel and Lodging$13.30 · 1 payment
Receiving payments does not imply wrongdoing. What Open Payments covers ·original records
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All 85 internal medicine physicians in Corona · All internal medicine physicians in California