Quick answers
- Which hospitals does Gerard Diefes work at?
- Medicare's official clinician data lists Gerard Diefes at 5 hospitals: Chester County Hospital, Hospital of University of Pennsylvania, Main Line Hospital Lankenau, Paoli Hospital and St Mary Medical Center. This is where the clinician works or has privileges; call the hospital to confirm.
- Where does Gerard Diefes see patients?
- Medicare's clinician data lists 3 practice locations, including Chalfont, PA, Lansdale, PA and King Of Prussia, PA. Call before your visit to confirm the address.
- What is Gerard Diefes's specialty?
- Medicare lists Pulmonary Disease as the primary specialty, and also Critical Care (Intensivists), Internal Medicine and Sleep Medicine.
- Does Gerard Diefes accept Medicare assignment?
- Yes. Medicare's clinician data says Gerard Diefes accepts Medicare assignment (the Medicare-approved amount as full payment for covered services), as of 2026-10-02. Ask the office to confirm before your visit.
- Does Gerard Diefes offer telehealth?
- Medicare's clinician data says Gerard Diefes offers telehealth services. Ask the office which visits can be done by video or phone.
- What is the phone number for Gerard Diefes?
- (215) 394-0400, as listed in official Medicare / NPI Registry data.
- What is Gerard Diefes's NPI number?
- 1417948951. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.
Hospitals where Gerard Diefes works
Medicare's Facility Affiliation Data lists Gerard Diefes at these hospitals (updated 2026-10-02). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians.
- Chester County HospitalWest Chester, PA · Acute Care Hospital · CCN 390179
- Hospital of University of PennsylvaniaPhiladelphia, PA · Acute Care Hospital · CCN 390111
- Main Line Hospital LankenauWynnewood, PA · Acute Care Hospital · CCN 390195
- Paoli HospitalPaoli, PA · Acute Care Hospital · CCN 390153
- St Mary Medical CenterLanghorne, PA · Acute Care Hospital · CCN 390258
Practice locations
Addresses where Gerard Diefes is enrolled with Medicare (CMS data updated 2026-10-02).
- 1100 Horizon CirChalfont, PA 18914 (215) 394‑0400
- 1240 S Broad St, 220 Pulm and Sleep SpecLansdale, PA 19446 (856) 234‑4436
- 860 1st Ave, Suite 9aKing Of Prussia, PA 19406 (856) 872‑7055
Group practices
Medicare enrollment lists Gerard Diefes as a member of this group (CMS data updated 2026-10-02).
- Advocare, LLC386 clinicians in the group
Specialties
- Pulmonary Diseaseprimary
- Critical Care (Intensivists)also
- Internal Medicinealso
- Sleep Medicinealso
Other pulmonologists in Pennsylvania
Clinicians with the same Medicare primary specialty in Pennsylvania — not a recommendation.
Clinician information
| Credential | MD |
|---|---|
| Medical school | Hahnemann University College Of Medicine |
| Graduation year | 1992 |
| Gender (as listed) | Male |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| Telehealth | Offers telehealth services |
| NPI (National Provider Identifier) | 1417948951 |
| Corrections | Report an error or suggest an update → |
Most corrections must be made at the source: clinicians update their NPI Registry record (NPPES) and their Medicare enrollment (PECOS); this page follows the next data release.
Sources
- Facility Affiliation Data — Centers for Medicare & Medicaid Services (CMS), data updated 2026-10-02, retrieved 2026-10-29
- National Downloadable File (Doctors and Clinicians) — CMS, data updated 2026-10-02, retrieved 2026-10-29
- NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
- Medicare Care Compare — official Medicare tool to look up clinicians