Douglas J. Grunwald, MD
NPI 1154616001ActiveIndividual· Internal Medicine, Gastroenterology· Hamden, CT
Internal Medicine, Gastroenterology (MD) in Hamden, Connecticut, trained at University of Chicago, Pritzker School of Medicine (class of 2011). Their prescriptions cost Medicare Part D more than their services did: $530,826 for 1,046 claims, against $214,609 paid for services in 2024. Madrigal Pharmaceuticals was the largest of 17 companies reporting payments in 2025, $1,657 in all, mostly food and beverage.
Overview
| NPI | 1154616001 |
|---|---|
| Status | Active |
| Entity type | Individual |
| Credential | MD |
| Sole proprietor | No |
| NPI issued | Jun 17, 2011 |
| Last updated in NPPES | Jul 21, 2022 |
| Certified by provider | May 27, 2021 |
Specialties and licenses
| Taxonomy | Code | License | State |
|---|---|---|---|
| Internal Medicine, Gastroenterology Primary | 207RG0100X | 56120 | CT |
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 - Gastroenterology (CT) |
|---|---|
| Accepts assignment | Yes (participating) |
Medicare services in 2024
| Medicare patients | 274 |
|---|---|
| Services billed | 10,087 across 44 procedure codes |
| Paid by Medicare | $214,609 |
Part D prescriptions in 2024
| Prescriptions (claims) | 1,046 · 2,262 30-day fills |
|---|---|
| Patients | 317 |
| Total drug cost | $530,826 |
| Generic share | 81% of claims |
Education and affiliations
| Medical school | University of Chicago, Pritzker School of Medicine |
|---|---|
| Graduation year | 2011 |
| Medicare specialty | Gastroenterology |
| Telehealth | Offers telehealth |
Medical group
- Hhc Physician Services PLLCHamden, CT · 132 clinicians
Hospital affiliation
- Yale-New Haven HospitalNew Haven, CT
Industry payments (Open Payments)
- 2025$1,657 · 75 payments from 17 companies
- 2024$1,223 · 59 payments from 17 companies
Top paying companies in 2025
| Company | Amount | Payments |
|---|---|---|
| Madrigal Pharmaceuticals | $289.87 | 13 |
| Ardelyx, Inc. | $268.52 | 11 |
| Abbvie Inc. | $148.34 | 11 |
| Qol Medical, LLC | $145.89 | 4 |
| Takeda Pharmaceuticals U.S.A., Inc. | $125.26 | 5 |
What the 2025 payments were for
- Food and Beverage$1,657 · 75 payments
Receiving payments does not imply wrongdoing. What Open Payments covers ·original records
Other Internal Medicine, Gastroenterology providers in Hamden
- 1023120326
- 1326140674
- 1770564247
- 1386975928
- 1225177769
- 1124045992
- 1558307025
- 1093080145
- 1851439848
- 1285070730
- 1770741290
- 1588830939
All Internal Medicine, Gastroenterology providers in Connecticut →