John Stephen Hammes, M.D.
Internal Medicine · Nephrology (CMS) · San Diego, CA
At a glance
8885 Rio San Diego Dr Ste 212, San Diego, CA 92108-1626
NPPES record updated Aug 19, 2026. Public records can lag behind changes at a practice.
Before you call: a quick checklist
- Are you accepting new patients?
- Do you accept my specific insurance plan?
- Do you provide the service I need at this address?
- Do I need a referral, and what is the earliest appointment?
Insurance participation and appointment availability are not established by these public records.
Medicare & insurance
Insurance participation is not established by these public records. Ask the practice and your insurer about your specific plan and this location.
How to check your coverage
Use your plan’s provider directory or the member-services number on your insurance card. Confirm the clinician, practice address, service, and whether a referral is required. A missing opt-out record does not establish Medicare acceptance.
Check the official Medicare directory ↗Practice location
8885 Rio San Diego Dr Ste 212San Diego, CA 92108-1626
Education & affiliations
- Medical / professional school
- Uniformed Services Uhs Fe Hebert School Of Med
- Graduation year
- 1993
- CMS specialties
- Internal Medicine · Nephrology
CMS reports telehealth services for this clinician. Confirm current services and availability with the practice.
Practice groups
Reported hospital affiliations
- Grossmont Hospital La Mesa, CA
- Scripps Mercy Hospital San Diego, CA
- Sharp Coronado Hospital And Hlthcr Ctr Coronado, CA
Graduation year does not establish years in practice. A reported affiliation does not establish employment, current admitting privileges, or insurance participation.
Source: CMS National Downloadable File · Published Oct 15, 2026.
Source: CMS Facility Affiliation Data · Published Oct 15, 2026.
Procedures in the public data
Reported activity can help you ask more informed questions about a practice’s services.
No displayed procedure-category record in this release. This does not mean the clinician performs no procedures.
CMS uses a one-year claims window with a reporting lag. Counts cover the Medicare activity included by CMS, not all patients. “1–10” is a published range. Volume is not a quality or outcomes score. Coverage and methodology
Source: CMS Utilization Data · Published Oct 15, 2026.
Find providers with a similar service mix
Compare 2024 published Medicare activity in the same reported specialty, here or in another city.
Industry-reported general payments
No matching general-payment summary in the imported release. This is not a verified zero and does not rule out other payment types or years.
Source: CMS 2025 payments grouped by covered recipient and nature of payments · Published Jun 30, 2026.
Professional details: NPI, taxonomy & registry record
Registry details
- Primary taxonomy
- Internal Medicine · Nephrology (CMS)
- Taxonomy code
- 207RN0300X
- Enumeration date
- Jan 28, 2006
- Record updated
- Aug 19, 2026
More registry details
- Provider type
- Individual · Type 1
- Reported credentials
- M.D.
Reported taxonomies and licenses
207RN0300X · Primary
License reported: G84351 CA
License numbers and credentials are reported to NPPES; HCPList does not independently verify them.
Practice location
8885 Rio San Diego Dr Ste 212San Diego, CA 92108-1626
- Phone
- (619) 299-2350
- Fax
- (619) 297-8379
Mailing address
9373 HAZARD WAY STE 200SAN DIEGO, CA 921231226
Information may be outdated or incomplete. Confirm details directly with the practice. HCPList is an independent directory and is not affiliated with CMS.
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