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Internal Medicine

Karisa Thayer, MD

Sees patients in National City, CA · California

Summary

Karisa Thayer, MD (Internal Medicine) is enrolled with Medicare at 1 practice location in National City, CA. NPI 1558765941. Medicare data says the clinician accepts Medicare assignment. Source: CMS National Downloadable File, updated 2026-10-02.

From official Medicare data

This page shows what Medicare's official clinician data says about Karisa Thayer, joined by NPI number (data updated 2026-10-02). It is not a recommendation or a rating. Call the office or hospital to confirm before you go.

In a medical emergency, call 911.

At a glance

Internal MedicinePrimary specialty
YesAccepts Medicare assignment
12Years since medical school (graduated 2014)
Loma Linda University School Of MedicineMedical school
FemaleGender (as listed)
Centro de Salud de la Comunidad de San Ysidro, Inc.Group practice

Quick answers

Where does Karisa Thayer see patients?
Medicare's clinician data lists 1 practice location in National City, CA. Call before your visit to confirm the address.
What is Karisa Thayer's specialty?
Medicare lists Internal Medicine as the primary specialty, and also Pediatric Medicine.
Does Karisa Thayer accept Medicare assignment?
Yes. Medicare's clinician data says Karisa Thayer accepts Medicare assignment (the Medicare-approved amount as full payment for covered services), as of 2026-10-02. Ask the office to confirm before your visit.
What is the phone number for Karisa Thayer?
(619) 662-4100, as listed in official Medicare / NPI Registry data.
What is Karisa Thayer's NPI number?
1558765941. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.

Practice locations

Addresses where Karisa Thayer is enrolled with Medicare (CMS data updated 2026-10-02).

Group practices

Medicare enrollment lists Karisa Thayer as a member of this group (CMS data updated 2026-10-02).

  • Centro de Salud de la Comunidad de San Ysidro, Inc.297 clinicians in the group

Specialties

Find other Internal Medicine doctors in California →

Other internal medicine doctors in National City

Clinicians with the same Medicare primary specialty in National City, CA — not a recommendation.

All internal medicine doctors in National City →

Clinician information

CredentialMD
Medical schoolLoma Linda University School Of Medicine
Graduation year2014
Gender (as listed)Female
Medicare assignmentAccepts (Medicare-approved amount as full payment)
NPI (National Provider Identifier)1558765941
CorrectionsReport an error or suggest an update →

Most corrections must be made at the source: clinicians update their NPI Registry record (NPPES) and their Medicare enrollment (PECOS); this page follows the next data release.

Sources

  1. National Downloadable File (Doctors and Clinicians) — CMS, data updated 2026-10-02, retrieved 2026-10-29
  2. NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
  3. Medicare Care Compare — official Medicare tool to look up clinicians