NPPES file of Aug 9, 2026

April Lynn Diep, DO

Family Medicine Physician · Walnut Creek, CA

April Lynn Diep, DO is a family medicine physician with a practice address in Walnut Creek, California, and NPI 1871933895, issued on Jul 5, 2013. Check the license (California 20A16610, 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
1871933895
Name
April Lynn Diep
Credential
DO
Primary taxonomy
Family Medicine Physician 207Q00000X
License number
20A16610 CA
Self-reported in NPPES; status is on the state search
Practice location
2621 Shadelands Dr, Walnut Creek, CA 94598
Phone
(925) 947-0417
Enumerated
Jul 5, 2013
Record last updated
Jun 13, 2026
Fax
(925) 947-4379
Medicare enrollment
Enrolled (PECOS I20190116002259); accepts Medicare assignment
Medical or professional school
Western University Of Health Sciences College Of Dental Med, 2013
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 2621 Shadelands Dr

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

  1. Karishma Bhardwaj, NP-CFamily Nurse Practitioner1083168439
  2. Josephine Chen, FNP, RNFamily Nurse Practitioner1790175214
  3. Noushin Haddad-Tehrani, MDInternal Medicine Physician1215988878
  4. Felix Vergilis, DOFamily Medicine Physician1144960592

Verify April Lynn Diep in five checks

  1. 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
  2. 2LicenseActive license and public ordersMedical Board of California
    Search for license 20A16610
    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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23% fewer Medicare Part D claims than the average family medicine physician in 2024

2,719 Medicare Part D claims for 368 beneficiaries, against an average of 3,544 among the 117,163 providers of this specialty who prescribed in Part D. Brand-name drugs were 8% of claims. 26 claims were for opioids.

  1. April Diep2,719
  2. Specialty average3,544

Most prescribed

  1. Levothyroxine Sodium240 claims
  2. Atorvastatin Calcium229 claims
  3. Amlodipine Besylate123 claims
  4. Losartan Potassium109 claims
  5. Lisinopril98 claims
  6. Escitalopram Oxalate80 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: $36.98

2 payments; by number, the most common kind was food and beverage; the largest payer was Abbvie Inc. The 55,478 providers of this specialty with any payment received $902.55 on average. Payments are reported by manufacturers, not by the provider, and are not a sign of wrongdoing.

  1. April Diep$36.98
  2. Specialty average$902.55

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. John Muir Physician NetworkWalnut Creek, CA

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

April Lynn Diep among 17,133 family medicine physician records in California

April Lynn Diep, DO is one of 17,133 family medicine physician records with a practice address in California. 81% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2013, is newer than 68% of them.

  • NPI issued2013 · 68% of these records are older, 29% newer
  • In a Medicare fileYes · 81% of these records are
  • In the CMS Doctors and Clinicians fileYes · 62% of these records are
  • Graduated2013 · median 2005 among the 10,652 with a school on file
  • Record last updated2026 · 58% of these records were not updated in five years or more

Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207Q00000X and a California practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).

116 family medicine physician records list a practice address in Walnut Creek

They are 116 of the 6,170 NPPES records with a practice address in Walnut Creek, and 17,133 family medicine physician records in California.

The 8 family medicine physician records with the nearest ZIP codes

  1. Taejoon Ahn, M.D.Walnut Creek, CA 945981639198757
  2. Leatrice Chang, MDWalnut Creek, CA 945981700822053
  3. John Crockett, M.D.Walnut Creek, CA 945981134221021
  4. Dennis Fong, M.D.Walnut Creek, CA 945981356364871
  5. Paul Kim, M.D.Walnut Creek, CA 945981609831163
  6. Pavani Kuruma, MDWalnut Creek, CA 945981285601310
  7. Franklin Long, MD MPHTMWalnut Creek, CA 945981194744045
  8. Timmothy Merrigan, M.D.Walnut Creek, CA 945981063442945

Common questions

What is April Lynn Diep, DO's NPI number?

April Lynn Diep, DO's National Provider Identifier (NPI) is 1871933895, issued on Jul 5, 2013. An NPI identifies a provider in billing; it is not a license.

Where is April Lynn Diep, DO located?

The NPPES record lists a practice address at 2621 Shadelands Dr, Walnut Creek, CA, 94598. Phone: (925) 947-0417. Providers update this record themselves, so call before visiting.

How can I verify April Lynn Diep, DO's license?

NPPES lists California license number 20A16610, 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 April Lynn Diep, DO prescribe under Medicare Part D?

In 2024, April Lynn Diep, DO had 2,719 Medicare Part D claims for 368 beneficiaries; the average among family medicine physician prescribers was 3,544. 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.