Quick answers
- Which hospitals does Alexander G. Chamessian work at?
- Medicare's official clinician data lists Alexander G. Chamessian at 5 hospitals: Barnes Jewish Hospital, Barnes-Jewish West County Hospital, Memorial Hospital, Missouri Baptist Medical Center and SSM St Joseph Hospital West. This is where the clinician works or has privileges; call the hospital to confirm.
- Where does Alexander G. Chamessian see patients?
- Medicare's clinician data lists 3 practice locations, including Lake St Louis, MO, Richmond Heights, MO and St Louis, MO. Call before your visit to confirm the address.
- What is Alexander G. Chamessian's specialty?
- Medicare lists Anesthesiology as the primary specialty, and also Physical Medicine and Rehabilitation.
- Does Alexander G. Chamessian accept Medicare assignment?
- Yes. Medicare's clinician data says Alexander G. Chamessian 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.
- What is the phone number for Alexander G. Chamessian?
- (636) 625-5200, as listed in official Medicare / NPI Registry data.
- What is Alexander G. Chamessian's NPI number?
- 1275194839. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.
Hospitals where Alexander G. Chamessian works
Medicare's Facility Affiliation Data lists Alexander G. Chamessian at these hospitals (updated 2026-10-02). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians.
- Barnes Jewish HospitalSaint Louis, MO · Acute Care Hospital · CCN 260032
- Barnes-Jewish West County HospitalCreve Coeur, MO · Acute Care Hospital · CCN 260162
- Memorial HospitalBelleville, IL · Acute Care Hospital · CCN 140185
- Missouri Baptist Medical CenterSaint Louis, MO · Acute Care Hospital · CCN 260108
- SSM St Joseph Hospital WestLake Saint Louis, MO · Acute Care Hospital · CCN 260200
Practice locations
Addresses where Alexander G. Chamessian is enrolled with Medicare (CMS data updated 2026-10-02).
- 100 Medical Plz, Fl 5Lake St Louis, MO 63367 (636) 625‑5200
- 1027 Bellevue AveRichmond Heights, MO 63117 (314) 768‑5202
- 1044 N Mason Rd, Dept Anes Pain Mgt Suite L30St Louis, MO 63141 (314) 996‑8631
Group practices
Medicare enrollment lists Alexander G. Chamessian as a member of these groups (CMS data updated 2026-10-02).
- Washington University3,029 clinicians in the group
- Post-Acute Physicians of Missouri, PC12 clinicians in the group
Specialties
Other anesthesiologists in Missouri
Clinicians with the same Medicare primary specialty in Missouri — not a recommendation.
Clinician information
| Credential | MD |
|---|---|
| Graduation year | 2019 |
| Gender (as listed) | Male |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| NPI (National Provider Identifier) | 1275194839 |
| 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