NPPES file of Aug 9, 2026

Karen Callen, M.D.

Specialist · San Francisco, CA

Karen Callen, M.D. is a specialist with a practice address in San Francisco, California, and NPI 1952459349, issued on Jan 8, 2007. Check the license (California A42176, as entered in NPPES) with the California board that licenses this profession; 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
1952459349
Name
Karen Callen
Credential
M.D.
Primary taxonomy
Specialist 174400000X
License number
A42176 CA
Self-reported in NPPES; status is on the state search
Practice location
1725 Montgomery St, San Francisco, CA 94111
Phone
(415) 831-2180
Enumerated
Jan 8, 2007
Record last updated
Aug 27, 2019 (not updated in 7 years: call before relying on the address or phone)
Fax
(415) 668-6970
Medicare enrollment
Enrolled (PECOS I20101221000936); may accept Medicare assignment
Medical or professional school
Tulane University School Of Medicine, 1984
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 1725 Montgomery St

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

  1. Milana Berguig, MDObstetrics & Gynecology Physician1902030414
  2. Jane Fang, M.D.Specialist1487702882
  3. Fung Lam, M.D.Specialist1225186620
  4. Lesley Meister, MDObstetrics & Gynecology Physician1811047244
  5. Hillary Mills, NP-CFamily Nurse Practitioner1831642784

Verify Karen Callen in five checks

  1. 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
  2. 2LicenseActive license and public ordersWhich California board licenses this profession
    Search for license A42176
    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
Find the California license search

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71% fewer Medicare Part D claims than the average specialist in 2024

403 Medicare Part D claims for 106 beneficiaries, against an average of 1,380 among the 8,233 providers of this specialty who prescribed in Part D. Brand-name drugs were 23% of claims.

  1. Karen Callen403
  2. Specialty average1,380

Most prescribed

  1. Estradiol89 claims
  2. Progesterone48 claims
  3. Estradiol (Twice Weekly)33 claims
  4. Valacyclovir29 claims
  5. Escitalopram Oxalate14 claims
  6. Premarin14 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: $506.88

20 payments; by number, the most common kind was food and beverage; the largest payer was Abbvie Inc. The 5,844 providers of this specialty with any payment received $4,760.79 on average. Payments are reported by manufacturers, not by the provider, and are not a sign of wrongdoing.

  1. Karen Callen$506.88
  2. Specialty average$4,760.79

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. Regents Univ OF California UcsfSan Francisco, CA

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

666 specialist records list a practice address in San Francisco

They are 666 of the 38,143 NPPES records with a practice address in San Francisco, and 5,749 specialist records in California.

Other specialist records in California

  1. Fatemeh Abbasi, PTVan Nuys, CA1558496760
  2. Erlinda Abcede, M.D.Cudahy, CA1831228675
  3. Maher Abdallah, M.D.Palm Springs, CA1205988011
  4. Farinaz AbdiSan Marcos, CA1063153963
  5. Mai Abe, LESanta Monica, CA1609405158
  6. Hamid Abedi, HEARING AID SPECIALISan Diego, CA1659410744
  7. Jonas AbellaSan Francisco, CA1679760938
  8. Shreedhar Abhyankar, M.D.Indio, CA1861530669
  9. Elaine AbichRiverside, CA1780458927
  10. Mussarat Abidi, MDLadera Ranch, CA1053307769

Common questions

What is Karen Callen, M.D.'s NPI number?

Karen Callen, M.D.'s National Provider Identifier (NPI) is 1952459349, issued on Jan 8, 2007. An NPI identifies a provider in billing; it is not a license.

Where is Karen Callen, M.D. located?

The NPPES record lists a practice address at 1725 Montgomery St, San Francisco, CA, 94111. Phone: (415) 831-2180. Providers update this record themselves, so call before visiting.

How can I verify Karen Callen, M.D.'s license?

NPPES lists California license number A42176, as entered by the provider. Search the California board that licenses this profession; the NPPES record confirms identity only.

How much does Karen Callen, M.D. prescribe under Medicare Part D?

In 2024, Karen Callen, M.D. had 403 Medicare Part D claims for 106 beneficiaries; the average among specialist prescribers was 1,380. 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.