Provider records sourced from NPPES (CMS National Plan & Provider Enumeration System). Data current as of October 4, 2026.
NPIDirectory

Joseph Detweiler, MD

Individual provider Student in an Organized Health Care Education/Training Program · NPI 1902484850

Joseph Detweiler, MD practises Internal Medicine in Thousand Oaks, California. Qualified in 2021, 5 years ago. Practices with Inpatient Specialists of California PC, a 364-clinician group and accepts Medicare assignment. Licensed in California.

Years since qualifying
5
Licensed in
CA
In the registry since
2021
Specialties on file
2
What do these letters mean?
MD — Doctor of Medicine
A physician who completed allopathic medical school.

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Practice location Address checks out

Student / training record This NPI belongs to someone enrolled in a health care training programme. It carries no licence and no practice of its own, so no address or phone number is published for it.

Thousand Oaks, CA

No coordinates on file. Search this address in Google Maps

Specialties & licences

Internal Medicine Physician (primary) Taxonomy 207R00000X · Licence A193411 (CA)
Student in an Organized Health Care Education/Training Program Taxonomy 390200000X

Record details

NPI number1902484850
Entity typeIndividual (Type 1)
GenderMale
Credentials MD
Sole proprietorYes
NPI enumeratedMarch 31, 2021
Last updated in NPPESJuly 31, 2024
Certification dateJuly 31, 2024

Medicare enrollment

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

Medicare specialtyINTERNAL MEDICINE
Medical schoolOTHER
Graduated 2021 (5 years in practice)
Group practice Inpatient Specialists Of California Pc — 364 clinicians
Accepts Medicare assignment Yes — accepts the Medicare-approved amount

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 patients78
Services billed 239 a service is one billed item, such as a visit, a test or a procedure
Average patient age79

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.

Payments from drug and device companies, 2025

Drug and device makers are required by federal law (the Physician Payments Sunshine Act) to report what they pay or give to clinicians, and CMS publishes the reports as Open Payments. This is the 2025 program year. A report is a record of a payment, not an allegation of anything, and many are small items such as meals. Only general payments are listed here; research payments and ownership or investment interests are reported separately by CMS and are not shown.

Food and Beverage $57 2 payments · a meal or drink at a meeting or visit, not a fee

Each amount is the sum of what companies reported for that kind of payment in 2025, rounded to the dollar. Not all of it is income to the clinician: a meal is not a fee, a charitable contribution goes to a charity, and a royalty or an acquisition payment is not a salary.

Check a report, or dispute one, at the source in CMS’s own tool, Open Payments. Corrections go through CMS’s dispute process. This site removes a home address on request and asks for no proof, because that is privacy; it will not remove an accurate payment report on request, because that is a statutory public disclosure.

Practises at

Facilities the CMS Facility Affiliation file lists for this clinician.

Colleagues at Inpatient Specialists of California PC

Clinicians the CMS Doctors & Clinicians file lists under the same group practice. CMS counts 364 clinicians in the practice; 12 are shown here.

Other providers in Thousand Oaks