Andrea S. Tieng, M.D.
NPI 1356528566ActiveIndividual· Internal Medicine, Gastroenterology· Rancho Cucamonga, CA
Internal Medicine, Gastroenterology (M.D.) in Rancho Cucamonga, California, licensed in CA and NY, with an NPI issued in January 2008. Their prescriptions cost Medicare Part D more than their services did: $260,655 for 902 claims, against $16,283 paid for services in 2024. Janssen Biotech, Inc. was the largest of 4 companies reporting payments in 2025, $134.22 in all, mostly food and beverage. Lists San Antonio Regional Hospital as a hospital affiliation.
Overview
| NPI | 1356528566 |
|---|---|
| Status | Active |
| Entity type | Individual |
| Credential | M.D. |
| Sole proprietor | Yes |
| NPI issued | Jan 30, 2008 |
| Last updated in NPPES | Jan 27, 2022 |
| Certified by provider | Jan 27, 2022 |
Specialties and licenses
| Taxonomy | Code | License | State |
|---|---|---|---|
| Internal Medicine, Gastroenterology Primary | 207RG0100X | A106477 | CA |
| Internal Medicine, Gastroenterology | 207RG0100X | 241597 | NY |
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 - Gastroenterology (CA) |
|---|---|
| Accepts assignment | Yes (participating) |
Medicare services in 2024
| Medicare patients | 98 |
|---|---|
| Services billed | 164 across 10 procedure codes |
| Paid by Medicare | $16,283 |
Part D prescriptions in 2024
| Prescriptions (claims) | 902 · 1,149 30-day fills |
|---|---|
| Patients | 619 |
| Total drug cost | $260,655 |
| Generic share | 80% of claims |
Education and affiliations
| Graduation year | 2003 |
|---|---|
| Medicare specialty | Gastroenterology |
Hospital affiliation
- San Antonio Regional HospitalUpland, CA
Industry payments (Open Payments)
- 2025$134.22 · 6 payments from 4 companies
- 2024$252.33 · 12 payments from 4 companies
Top paying companies in 2025
| Company | Amount | Payments |
|---|---|---|
| Janssen Biotech, Inc. | $49.06 | 2 |
| Braintree Laboratories, Inc. | $36.00 | 2 |
| Intercept Pharmaceuticals, Inc. | $29.57 | 1 |
| Novo Nordisk Inc | $19.59 | 1 |
What the 2025 payments were for
- Food and Beverage$134.22 · 6 payments
Receiving payments does not imply wrongdoing. What Open Payments covers ·original records
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