NPPES file of Aug 9, 2026

Mahtab Naji, MD

Internal Medicine Physician · San Clemente, CA

Mahtab Naji, MD is an internal medicine physician with a practice address in San Clemente, California, and NPI 1558949693, issued on Mar 30, 2021. Check the license (California A189001, as entered in NPPES) on the Medical Board of California; the Medicare figures below come from public CMS files.

Record from CMS NPPES, file of Aug 9, 2026 · Medicare files 2024 · method · Verify with CMS →

NPPES recordNPPES file of Aug 9, 2026
1558949693
Name
Mahtab Naji
Credential
MD
Primary taxonomy
Internal Medicine Physician 207R00000X
License number
A189001 CA
Self-reported in NPPES; status is on the state search
Practice location
638 Camino DE Los Mares Ste D4, San Clemente, CA 92673
Phone
(949) 542-8865
Enumerated
Mar 30, 2021
Record last updated
Aug 8, 2024
Medicare enrollment
Enrolled (PECOS I20231226001466); accepts Medicare assignment
Telehealth
Offers telehealth (CMS)
Entity
Type 1 · individual
Public record from CMS NPPES (open it on the CMS NPI Registry). Enrollment, assignment, school and telehealth: CMS Doctors and Clinicians file, Aug 2026. A record is not a license: verify it with the state board.
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Also registered at 638 Camino DE Los Mares Ste D4

A shared address usually means a shared clinic or building; it does not show who employs whom.

  1. Hitesh Patel, MDNeurological Surgery Physician1053573519

Verify Mahtab Naji in five checks

  1. 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
  2. 2LicenseActive license and public ordersMedical Board of California
    Search for license A189001
    Check the board
  3. 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
  4. 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
  5. 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
Open the California license search

PlainDoctor does not match the HHS-OIG exclusion list to individual records: most entries carry no NPI. Search the OIG exclusion list by name.

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75% fewer Medicare Part D claims than the average internal medicine physician in 2024

796 Medicare Part D claims for 263 beneficiaries, against an average of 3,176 among the 108,855 providers of this specialty who prescribed in Part D.

  1. Mahtab Naji796
  2. Specialty average3,176

Most prescribed

  1. Atorvastatin Calcium52 claims
  2. Levothyroxine Sodium43 claims
  3. Amlodipine Besylate42 claims
  4. Pantoprazole Sodium36 claims
  5. Losartan Potassium34 claims
  6. Rosuvastatin Calcium33 claims

Source: CMS Medicare Part D Prescribers by Provider and Drug, 2024 (data.cms.gov). Part D covers prescriptions for Medicare patients only; drugs with fewer than 11 claims are not published.

Industry payments in 2024: $14.87

1 payment: food and beverage; the largest payer was Teva Pharmaceuticals USA, Inc. The 50,334 providers of this specialty with any payment received $1,303.06 on average. Payments are reported by manufacturers, not by the provider, and are not a sign of wrongdoing.

  1. Mahtab Naji$14.87
  2. Specialty average$1,303.06

Source: CMS Open Payments, program year 2024 (openpaymentsdata.cms.gov); average among providers of this specialty with at least one payment.

Bills Medicare through one group practice

  1. Memorialcare Medical FoundationSan Clemente, CA

Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).

Mahtab Naji among 17,696 internal medicine physician records in California

Mahtab Naji, MD is one of 17,696 internal medicine physician records with a practice address in California. 79% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2021, is newer than 92% of them.

  • NPI issued2021 · 92% of these records are older, 5% newer
  • In a Medicare fileYes · 79% of these records are
  • In the CMS Doctors and Clinicians fileYes · 63% of these records are
  • Graduated2016 · median 2004 among the 11,065 with a school on file
  • Record last updated2024 · 61% of these records were not updated in five years or more

Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207R00000X and a California practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).

16 internal medicine physician records list a practice address in San Clemente

They are 16 of the 969 NPPES records with a practice address in San Clemente, and 17,696 internal medicine physician records in California.

The 8 internal medicine physician records with the nearest ZIP codes

  1. Greg Brown, M.D.San Clemente, CA 926731720135346
  2. Lawrence Chang, M.D.San Clemente, CA 926731528046430
  3. Steven Cullen, MDSan Clemente, CA 926731487765731
  4. Karen Garner, MDSan Clemente, CA 926731770639189
  5. Nick Karahalios, MDSan Clemente, CA 926731255442505
  6. Seema Khan, M.DSan Clemente, CA 926731376795617
  7. Torsten Kruse, M.D.San Clemente, CA 926731972644482
  8. Simon Outhwaite, MDSan Clemente, CA 926731851402002

Common questions

What is Mahtab Naji, MD's NPI number?

Mahtab Naji, MD's National Provider Identifier (NPI) is 1558949693, issued on Mar 30, 2021. An NPI identifies a provider in billing; it is not a license.

Where is Mahtab Naji, MD located?

The NPPES record lists a practice address at 638 Camino DE Los Mares Ste D4, San Clemente, CA, 92673. Phone: (949) 542-8865. Providers update this record themselves, so call before visiting.

How can I verify Mahtab Naji, MD's license?

NPPES lists California license number A189001, as entered by the provider. Search the Medical Board of California at https://www.mbc.ca.gov/License-Verification/default.aspx. The NPPES record confirms identity only; the state search shows license status, expiration and public orders.

How much does Mahtab Naji, MD prescribe under Medicare Part D?

In 2024, Mahtab Naji, MD had 796 Medicare Part D claims for 263 beneficiaries; the average among internal medicine physician prescribers was 3,176. Part D covers Medicare prescriptions only.

Source: CMS National Plan and Provider Enumeration System (NPPES), file of Aug 9, 2026 (NPPES files on CMS.gov); NUCC Health Care Provider Taxonomy. Medicare files from data.cms.gov. An NPI identifies who bills; it is not a license.

Figures on PlainDoctor are read from the federal files each page names (CMS NPPES, Medicare Part D, MIPS, Open Payments; the HHS-OIG exclusion list only as counts) and from Census population estimates, with the file date shown beside them. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of Aug 9, 2026.