Mark D. Weissig, M.D.
NPI 1649266032ActiveIndividual· Internal Medicine, Pulmonary Disease· Fullerton, CA
Internal Medicine, Pulmonary Disease (M.D.) in Fullerton, California, trained at Duke University School of Medicine (class of 1980). Their prescriptions cost Medicare Part D more than their services did: $1,728,888 for 5,274 claims, against $121,546 paid for services in 2024. Astrazeneca Pharmaceuticals LP was the largest of 3 companies reporting payments in 2025, $423.55 in all, mostly food and beverage.
Overview
| NPI | 1649266032 |
|---|---|
| Status | Active |
| Entity type | Individual |
| Credential | M.D. |
| Sole proprietor | No |
| NPI issued | Sep 21, 2005 |
| Last updated in NPPES | Apr 25, 2013 |
Specialties and licenses
| Taxonomy | Code | License | State |
|---|---|---|---|
| Internal Medicine, Pulmonary Disease Primary | 207RP1001X | G49175 | CA |
| Internal Medicine | 207R00000X | G49175 | CA |
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 - Pulmonary Disease (CA) |
|---|---|
| Accepts assignment | Yes (participating) |
Medicare services in 2024
| Medicare patients | 529 |
|---|---|
| Services billed | 1,616 across 18 procedure codes |
| Paid by Medicare | $121,546 |
Part D prescriptions in 2024
| Prescriptions (claims) | 5,274 · 9,446 30-day fills |
|---|---|
| Patients | 788 |
| Total drug cost | $1,728,888 |
| Generic share | 63% of claims |
Education and affiliations
| Medical school | Duke University School of Medicine |
|---|---|
| Graduation year | 1980 |
| Medicare specialty | Pulmonary Disease |
| Telehealth | Offers telehealth |
Medical group
- Providence Medical FoundationVictorville, CA · 1,466 clinicians
Hospital affiliations
- Providence St. Joseph HospitalOrange, CA
- Providence St. Jude Medical CenterFullerton, CA
Industry payments (Open Payments)
- 2025$423.55 · 28 payments from 3 companies
- 2024$345.63 · 24 payments from 3 companies
Top paying companies in 2025
| Company | Amount | Payments |
|---|---|---|
| Astrazeneca Pharmaceuticals LP | $192.52 | 18 |
| Glaxosmithkline, LLC. | $120.47 | 5 |
| Boehringer Ingelheim Pharmaceuticals, Inc. | $110.56 | 5 |
What the 2025 payments were for
- Food and Beverage$423.55 · 28 payments
Receiving payments does not imply wrongdoing. What Open Payments covers ·original records
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