Howard Guan, M.D.
NPI 1134427636ActiveIndividual· Ophthalmology, Glaucoma Specialist· San Marcos, CA
Ophthalmology, Glaucoma Specialist (M.D.) in San Marcos, California, trained at Loma Linda University School of Medicine (class of 2010). In 2024 Medicare paid $301,772 for 392 patients, and Part D covered 2,586 of their prescriptions, 63% of them generic. Dompe US, Inc. was the largest of 6 companies reporting payments in 2025, $790.19 in all, mostly food and beverage.
Overview
| NPI | 1134427636 |
|---|---|
| Status | Active |
| Entity type | Individual |
| Credential | M.D. |
| Sole proprietor | No |
| NPI issued | Mar 7, 2011 |
| Last updated in NPPES | Oct 21, 2025 |
| Certified by provider | Oct 21, 2025 |
Specialties and licenses
| Taxonomy | Code | License | State |
|---|---|---|---|
| Ophthalmology, Glaucoma Specialist Primary | 207WX0009X | A119766 | CA |
| Ophthalmology | 207W00000X | A119766 | 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 - Ophthalmology (CA) |
|---|---|
| Accepts assignment | Yes (participating) |
Medicare services in 2024
| Medicare patients | 392 |
|---|---|
| Services billed | 6,898 across 56 procedure codes |
| Paid by Medicare | $301,772 |
Part D prescriptions in 2024
| Prescriptions (claims) | 2,586 · 4,321 30-day fills |
|---|---|
| Patients | 671 |
| Total drug cost | $435,142 |
| Generic share | 63% of claims |
Education and affiliations
| Medical school | Loma Linda University School of Medicine |
|---|---|
| Graduation year | 2010 |
| Medicare specialty | Ophthalmology |
Medical group
- Tory Prestera MD Inc.San Marcos, CA · 3 clinicians
Industry payments (Open Payments)
- 2025$790.19 · 26 payments from 6 companies
- 2024$946.06 · 22 payments from 7 companies
Top paying companies in 2025
| Company | Amount | Payments |
|---|---|---|
| Dompe US, Inc. | $220.60 | 9 |
| Astellas Pharma US Inc | $166.65 | 2 |
| Abbvie Inc. | $165.45 | 10 |
| Johnson & Johnson Surgical Vision, Inc. | $136.95 | 1 |
| Alcon Vision LLC | $71.68 | 3 |
What the 2025 payments were for
- Food and Beverage$790.19 · 26 payments
Receiving payments does not imply wrongdoing. What Open Payments covers ·original records