Alan W. Chang, MD
NPI 1912992330ActiveIndividual· Internal Medicine, Gastroenterology· Doylestown, PA
Internal Medicine, Gastroenterology (MD) with Via Affiliates and 1 other group, practicing in Doylestown, Pennsylvania. Their prescriptions cost Medicare Part D more than their services did: $919,546 for 1,319 claims, against $257,317 paid for services in 2024. Ardelyx, Inc. was the largest of 10 companies reporting payments in 2025, $551.89 in all, mostly food and beverage. Lists Doylestown Hospital as a hospital affiliation.
Overview
| NPI | 1912992330 |
|---|---|
| Status | Active |
| Entity type | Individual |
| Credential | MD |
| Sole proprietor | No |
| NPI issued | Sep 12, 2005 |
| Last updated in NPPES | Feb 28, 2020 |
| Certified by provider | Feb 28, 2020 |
Specialties and licenses
| Taxonomy | Code | License | State |
|---|---|---|---|
| Internal Medicine, Gastroenterology Primary | 207RG0100X | MD071986L | PA |
| Specialist | 174400000X | MD071986L | PA |
Exclusion screening
| List | Result | Details |
|---|---|---|
| HHS-OIG LEIE · Oct 9, 2026 | No match | Checked by NPI and by name + state |
| North Carolina Medicaid · Nov 10, 2026 | No match | — |
| New York OMIG · Nov 10, 2026 | No match | — |
| Ohio Medicaid · Nov 10, 2026 | No match | — |
| Pennsylvania Medicheck · Nov 10, 2026 | No match | — |
| Washington HCA · Nov 10, 2026 | No match | — |
Official OIG search · How matching works ·Bulk check a roster
Medicare
| Enrollment (PECOS) | Enrolled Practitioner - Gastroenterology (PA) |
|---|---|
| Accepts assignment | Yes (participating) |
Medicare services in 2024
| Medicare patients | 673 |
|---|---|
| Services billed | 7,956 across 43 procedure codes |
| Paid by Medicare | $257,317 |
Part D prescriptions in 2024
| Prescriptions (claims) | 1,319 · 2,617 30-day fills |
|---|---|
| Patients | 429 |
| Total drug cost | $919,546 |
| Generic share | 79% of claims |
Education and affiliations
| Graduation year | 1998 |
|---|---|
| Medicare specialty | Gastroenterology |
| Secondary specialties | Internal Medicine |
| Telehealth | Offers telehealth |
Medical groups
- Via AffiliatesDoylestown, PA · 180 clinicians
- Clinical Specialty AssociatesDoylestown, PA · 171 clinicians
Hospital affiliation
- Doylestown HospitalDoylestown, PA
Industry payments (Open Payments)
- 2025$551.89 · 22 payments from 10 companies
- 2024$3,365 · 139 payments from 29 companies
Top paying companies in 2025
| Company | Amount | Payments |
|---|---|---|
| Ardelyx, Inc. | $163.95 | 3 |
| Abbvie Inc. | $129.73 | 7 |
| Ipsen Biopharmaceuticals, Inc | $63.02 | 3 |
| Salix Pharmaceuticals, A Division of Bausch Health US, LLC | $56.50 | 3 |
| Braintree Laboratories, Inc. | $31.02 | 1 |
What the 2025 payments were for
- Food and Beverage$551.89 · 22 payments
Receiving payments does not imply wrongdoing. What Open Payments covers ·original records
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