Alexander Horwitz, MD
Psychiatry Physician · Napa, CA
Alexander Horwitz, MD is a psychiatry physician with a practice address in Napa, California, and NPI 1891317954, issued on May 12, 2020. Check the license (California A181639, as entered in NPPES) on the Medical Board of California; the Medicare figures below come from public CMS files.
- Name
- Alexander Horwitz
- Credential
- MD
- Primary taxonomy
- Psychiatry Physician 2084P0800X
- License number
- A181639 CA
Self-reported in NPPES; status is on the state search - Practice location
- 2100 Napa Vallejo Hwy, Napa, CA 94558
- Phone
- (707) 253-5000
- Enumerated
- May 12, 2020
- Record last updated
- Aug 10, 2025
- Entity
- Type 1 · individual
8 nearest psychiatry physician records → All 8,673 in California → Look up another NPI →
Also registered at 2100 Napa Vallejo Hwy
A shared address usually means a shared clinic or building; it does not show who employs whom.
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- Ali Akhavan, MDInternal Medicine Physician1013943174
- Barbara Bachmeier, PSYDClinical Psychologist1902039829
Verify Alexander Horwitz in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMedical Board of California
Search for license A181639Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
93% fewer Medicare Part D claims than the average psychiatry physician in 2024
73 Medicare Part D claims for 16 beneficiaries, against an average of 1,000 among the 35,054 providers of this specialty who prescribed in Part D.
Most prescribed
- Trazodone Hcl24 claims
- Duloxetine Hcl19 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.
Alexander Horwitz among 8,673 psychiatry physician records in California
Alexander Horwitz, MD is one of 8,673 psychiatry physician records with a practice address in California. 67% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2020, is newer than 87% of them.
- NPI issued2020 · 87% of these records are older, 9% newer
- In a Medicare fileYes · 67% of these records are
- In the CMS Doctors and Clinicians fileNo · 38% of these records are
- Record last updated2025 · 54% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 2084P0800X and a California practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
97 psychiatry physician records list a practice address in Napa
They are 97 of the 3,583 NPPES records with a practice address in Napa, and 8,673 psychiatry physician records in California.
All 8,673 in California → Every provider in Napa → Psychiatry Physician nationwide →
The 8 psychiatry physician records with the nearest ZIP codes
- Noorulain Aqeel, MDNapa, CA 945581811949944
- Victoria Cabanela, M.D.Napa, CA 945581407808819
- Lilian Dalida, MDNapa, CA 945581235181637
- Richard Frishman, MDNapa, CA 945581174507347
- Ahmed Haggag, MDNapa, CA 945581225080674
- Ernest Hanes, M. D.Napa, CA 945581659361574
- Eric Khoury, MDNapa, CA 945581972555274
- Sunil Kishan, MDNapa, CA 945581578515979
Common questions
What is Alexander Horwitz, MD's NPI number?
Alexander Horwitz, MD's National Provider Identifier (NPI) is 1891317954, issued on May 12, 2020. An NPI identifies a provider in billing; it is not a license.
Where is Alexander Horwitz, MD located?
The NPPES record lists a practice address at 2100 Napa Vallejo Hwy, Napa, CA, 94558. Phone: (707) 253-5000. Providers update this record themselves, so call before visiting.
How can I verify Alexander Horwitz, MD's license?
NPPES lists California license number A181639, 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 Alexander Horwitz, MD prescribe under Medicare Part D?
In 2024, Alexander Horwitz, MD had 73 Medicare Part D claims for 16 beneficiaries; the average among psychiatry physician prescribers was 1,000. 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.