Provider records sourced from NPPES (CMS National Plan & Provider Enumeration System). Data current as of August 10, 2026.

James Lewis Zehnder, MD

Individual provider Hematology (Internal Medicine) Physician · NPI 1669508826

James Lewis Zehnder, MD practises Pathology in Stanford, California. Graduated from Tufts University School of Medicine in 1984, 42 years ago. Practices with Stanford Health Care, a 3,085-clinician group, accepts Medicare assignment and offers telehealth. Licensed in California.

Years since qualifying
42
Trained at
Tufts University School of Medicine
Licensed in
CA
In the registry since
2007
Specialties on file
4
What do these letters mean?
MD — Doctor of Medicine
A physician who completed allopathic medical school.

See every abbreviation used in this directory →

Practice location Address checks out

300 Pasteur Dr
Stanford, CA 94305-2200
Phone: (650) 723-4000
Show map & directions

Pin is approximate — placed at the ZIP-code centre, not the exact door.

Specialties & licences

Anatomic Pathology Physician (primary) Taxonomy 207ZP0101X · Licence G56192 (CA)
Hematology (Internal Medicine) Physician Taxonomy 207RH0000X · Licence G56192 (CA)
Internal Medicine Physician Taxonomy 207R00000X · Licence G56192 (CA)
Anatomic Pathology & Clinical Pathology Physician Taxonomy 207ZP0102X · Licence G55192 (CA)

Record details

NPI number1669508826
Entity typeIndividual (Type 1)
GenderMale
Credentials MD
Sole proprietorNo
NPI enumeratedFebruary 24, 2007
Last updated in NPPESMarch 13, 2024
Certification dateMarch 13, 2024

Medicare enrollment

From the CMS Doctors & Clinicians file — this clinician is enrolled in Medicare.

Medicare specialtyPATHOLOGY
Also practisesHEMATOLOGY
Medical schoolTUFTS UNIVERSITY SCHOOL OF MEDICINE
Graduated 1984 (42 years in practice)
Group practice Stanford Health Care — 3085 clinicians
Accepts Medicare assignment Yes — accepts the Medicare-approved amount
TelehealthOffers telehealth services
Practice locations2 on file with Medicare

Medicare patients and services, 2024

From the CMS Medicare Physician & Other Practitioners file for calendar year 2024. It counts Original Medicare patients only, so a practice that mostly sees Medicare Advantage or privately insured patients looks smaller here than it is.

Medicare patients1,144
Services billed 1,554 a service is one billed item, such as a visit, a test or a procedure
Average patient age75

Dollar amounts are not shown. What Medicare pays a practice is gross billings, before staff, premises and tax and including the cost of any drugs it administers, so it is not what a clinician earns.

Practises at

Facilities the CMS Facility Affiliation file lists for this clinician.

Colleagues at Stanford Health Care

Clinicians the CMS Doctors & Clinicians file lists under the same group practice. CMS counts 3085 clinicians in the practice; 12 are shown here.

Other providers in Stanford