GREGORY KRASTEIN MD
NPI 1942358759
Internal Medicine - Nephrology in Oxnard, CA
About Gregory Krastein Md NPPES
Official registry information on file with the National Plan and Provider Enumeration System.
GREGORY KRASTEIN MD (NPI 1942358759) is an individual nephrology provider in Oxnard, California, licensed in California (G70211) and active in the NPI registry since January 2007. He is enrolled in Medicare PECOS, maintains a secondary practice location in Woodland Hills, and is a graduate of George Washington University School Of Medicine (1990).
NPPES Registry Identity
Specialties & Licenses
Secondary Practice Location 1
Medicare Participation & PECOS CMS
Medicare enrollment, assignment, billing reassignment, and ordering and referring status from CMS.
Medicare Enrollment Status
Enrolled in Medicare and accepts Medicare assignment
Gregory Krastein Md is registered in PECOS and agrees to accept the Medicare-approved amount as full payment. Medicare patients are not billed beyond the standard deductible and coinsurance.
Medicare Billing Reassignments
2Medicare enrollment records show Gregory Krastein reassigns Medicare billing to 2 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.
Oxnard, CA 93036
- Reassigned Medicare billing, California enrollment
- 13,921 clinicians in this Medicare group
Honolulu, HI 96819
- Reassigned Medicare billing, Hawaii enrollment
- 1,187 clinicians in this Medicare group
Source: CMS Revalidation Reassignment List, October 2026 release. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.
Areas of Expertise CMS Part B claims 2
Services this provider delivered to Medicare fee-for-service patients, from the CMS Medicare utilization data. Higher counts generally reflect more experience with a service; care delivered outside Medicare is not included.
Physician Visit Costs CMS claims · ZIP area
Typical Medicare office-visit costs in the 93036 ZIP code area, from fee-for-service claims. These are area statistics, not this provider’s prices; actual charges vary by service and coverage.
Other Providers at the Same Location NPPES 3
Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.
OXNARD, CA 93036
Frequently Asked Questions NPPES & CMS
Common questions about this NPI record, answered from the official NPPES registry and CMS datasets shown on this page.
What is Gregory Krastein's NPI number?
The NPI number for Gregory Krastein is 1942358759. It was assigned to this individual provider in the NPPES registry on January 8, 2007.
Where is Gregory Krastein located?
Gregory Krastein practices at 2103 E Gonzales Rd, Oxnard, CA 93036. The listed phone number is (805) 822-4595.
What is Gregory Krastein's specialty?
The primary specialty registered for this NPI is Internal Medicine, specializing in Nephrology, with taxonomy code 207RN0300X.
Is Gregory Krastein enrolled in Medicare?
Yes. Gregory Krastein is registered in the Medicare PECOS system and accepts Medicare assignment, which means accepting the Medicare-approved amount as payment in full for covered services.
Which organizations bill Medicare for Gregory Krastein's services?
According to the CMS Revalidation Reassignment List (October 2026 release), Gregory Krastein reassigns Medicare benefits to 2 organizations: Southern California Permanente Medical Group (Oxnard, CA) and Hawaii Permanente Medical Group Inc (Honolulu, HI). Each reassignment is filed with Medicare on form CMS-855R, signed by both the clinician and the organization, and lets the organization bill Medicare and receive payment for Gregory Krastein's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.
When was this NPI record last updated?
The NPPES record for Gregory Krastein was last updated on February 21, 2023. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 3 years ago. If this record has changed at CMS more recently, you can request an on-demand re-check against the live CMS registry, directly from this page.
# Gregory Krastein, MD · NPI 1942358759
Nephrology physician in Oxnard, California. Individual provider, active in the CMS NPPES registry since January 8, 2007.
## Identity
- **NPI:** 1942358759 (Entity type: Individual)
- **Enumerated:** January 8, 2007
- **Primary specialty:** Internal Medicine - Nephrology · taxonomy 207RN0300X
- **State license:** G70211 (California)
- **Sole proprietor:** No
## Practice location
- **Address:** 2103 E GONZALES RD, Oxnard, CA 93036-3757
- **Phone:** (805) 822-4595
## Medicare
- **Medicare:** Enrolled (PECOS); accepts Medicare assignment
- **Ordering & referring:** eligible for Part B labs & imaging, durable medical equipment, home health, power mobility devices
- **Bills Medicare through:** 2 organizations under Medicare reassignment (form CMS-855R): Southern California Permanente Medical Group (NPI 1275756652, Oxnard, CA); Hawaii Permanente Medical Group Inc (NPI 1710945969, Honolulu, HI) · CMS Revalidation Reassignment List, October 2026 release
- **Medical school:** George Washington University School Of Medicine, class of 1990
## Record status
- **NPPES last updated:** February 21, 2023
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Source: [NPI Profile](https://npiprofile.com/npi/1942358759) · Data from the CMS NPPES public registry.