Quick answers
- Where does John J. Ryu see patients?
- Medicare's clinician data lists 2 practice locations, including Walnut Creek, CA and San Jose, CA. Call before your visit to confirm the address.
- What is John J. Ryu's specialty?
- Medicare lists Anesthesiology as the primary specialty.
- Does John J. Ryu accept Medicare assignment?
- Yes. Medicare's clinician data says John J. Ryu 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 John J. Ryu?
- (925) 935-6700, as listed in official Medicare / NPI Registry data.
- What is John J. Ryu's NPI number?
- 1497783021. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.
Practice locations
Addresses where John J. Ryu is enrolled with Medicare (CMS data updated 2026-10-02).
- 2405 Shadelands Dr, Suite 200Walnut Creek, CA 94598 (925) 935‑6700
- 2425 Samaritan DrSan Jose, CA 95124 (408) 559‑2011
Group practices
Medicare enrollment lists John J. Ryu as a member of these groups (CMS data updated 2026-10-02).
- Cep America - Anesthesia PC849 clinicians in the group
- G2 Anesthesia PC107 clinicians in the group
Specialties
- Anesthesiologyprimary
Other anesthesiologists in Walnut Creek
Clinicians with the same Medicare primary specialty in Walnut Creek, CA — not a recommendation.
Clinician information
| Credential | MD |
|---|---|
| Medical school | Vanderbilt University School Of Medicine |
| Graduation year | 1991 |
| Gender (as listed) | Male |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| NPI (National Provider Identifier) | 1497783021 |
| 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
- 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