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FRANK T GRASSI M.D.
NPI 1649320821
Internal Medicine - Critical Care Medicine in San Diego, CA

Active since January 11, 2007
4033 3RD AVE STE 300, SAN DIEGO, CA 92103(619) 299-2570(619) 294-2738 Get Directions Write a Review

NPPES record last updated: September 11, 2025. Verified against the NPPES registry weekly; last sync: August 02, 2026.

Record update history: Sep 11, 2025, Aug 22, 2020 (2 updates tracked since 2020).

About Frank T Grassi M.d. NPPES

Official registry information on file with the National Plan and Provider Enumeration System.

FRANK T GRASSI M.D. (NPI 1649320821) is a healthcare organization registered as a critical care medicine in San Diego, California and active in the NPI registry since January 2007. The organization lists Melissa Miller, Medical Biller, as its authorized official.

NPPES Registry Identity

NPI1649320821
Entity TypeOrganization
Primary Taxonomy207RC0200X
Legal Business NameFRANK T GRASSI M.D.
Location Address4033 3RD AVE STE 300San Diego, CA 92103-2138
Mailing Address4033 3rd Ave Ste 300San Diego, CA 92103-2138 · (619) 299-2570 · Fax (619) 294-2738
Phone(619) 299-2570
Fax(619) 294-2738
Organization SubpartNo
Authorized OfficialMelissa MillerMedical Biller · (619) 299-2570
Enumeration DateJanuary 11, 2007
Last NPPES UpdateSeptember 11, 20252 updates tracked since enumeration
✔ NPI 1649320821 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses 2

★ Primary SpecialtyInternal Medicine · Critical Care MedicineAllopathic & Osteopathic Physicians
Taxonomy Code207RC0200X
Definition
An internist who diagnoses, treats and supports patients with multiple organ dysfunction. This specialist may have administrative responsibilities for intensive care units and may also facilitate and coordinate patient care among the primary physician, the critical care staff and other specialists.
Also ListedInternal Medicine · Pulmonary DiseaseTaxonomy 207RP1001X
4033 3RD AVE STE 300, San Diego, CA 92103
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Group Practice 1

Group TaxonomyThis provider is a business group of one or more individual practitioners, who practice with different areas of specialization.193200000X MULTI-SPECIALTY GROUP

Other Providers at the Same Location NPPES 2

Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.

JOSEPH RESNIKOFF, M.D., F.C.C.P.
Internal Medicine (Critical Care Medicine)
4033 3RD AVE STE 300
SAN DIEGO, CA 92103
San Diego County (619) 299-2570
CHRISTOPHER M STAFFORD M.D.
Internal Medicine (Critical Care Medicine)
4033 3RD AVE STE 300
SAN DIEGO, CA 92103
San Diego County (619) 299-2570

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 Frank T Grassi M.D.'s NPI number?

The NPI number for Frank T Grassi M.D. is 1649320821. It was assigned to this organization in the NPPES registry on January 11, 2007.

Where is Frank T Grassi M.D. located?

Frank T Grassi M.D. is located at 4033 3rd Ave Ste 300, San Diego, CA 92103. The listed phone number is (619) 299-2570.

What is Frank T Grassi M.D.'s specialty?

The primary specialty registered for this NPI is Internal Medicine, specializing in Critical Care Medicine, with taxonomy code 207RC0200X.

When was this NPI record last updated?

The NPPES record for Frank T Grassi M.D. was last updated on September 11, 2025. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 10 months 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.