NPPES file of Aug 9, 2026

Michael A. Amster, MD

Pain Medicine Physician · Santa Cruz, CA

Michael A. Amster, MD is a pain medicine physician with a practice address in Santa Cruz, California, and NPI 1114023058, issued on Sep 16, 2006. Check the license (California A81550, 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
1114023058
Name
Michael A. Amster
Credential
MD
Primary taxonomy
Pain Medicine Physician 208VP0000X
License number
A81550 CA
Self-reported in NPPES; status is on the state search
Practice location
1510 Capitola RD, Santa Cruz, CA 95062
Phone
(831) 427-3500
Enumerated
Sep 16, 2006
Record last updated
Dec 7, 2022
Medicare enrollment
Enrolled (PECOS I20051101001141); accepts Medicare assignment
Medical or professional school
University Of California, Irvine, California College Of Medicine, 2001
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 1510 Capitola RD

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

  1. Nadia AllamiPediatric Nurse Practitioner1346723087
  2. Jacqueline AlvarezMarriage & Family Therapist1093436511
  3. Krystina Begonia, MDFamily Medicine Physician1760942734
  4. Rebecca Breton, MDPediatrics Physician1659367548
  5. Karen Carranza, RNRegistered Nurse1013730001
  6. Catherine Cashatt, RNRegistered Nurse1396614640

Verify Michael A. Amster in five checks

  1. 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
  2. 2LicenseActive license and public ordersMedical Board of California
    Search for license A81550
    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

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86% fewer Medicare Part D claims than the average pain medicine physician in 2024

302 Medicare Part D claims for 48 beneficiaries, against an average of 2,095 among the 944 providers of this specialty who prescribed in Part D. 188 claims were for opioids.

  1. Michael Amster302
  2. Specialty average2,095

Most prescribed

  1. Tramadol Hcl43 claims
  2. Oxycodone Hcl41 claims
  3. Hydrocodone-Acetaminophen33 claims
  4. Morphine Sulfate Er32 claims
  5. Duloxetine Hcl24 claims
  6. Gabapentin19 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: $167.50

5 payments; by number, the most common kind was food and beverage; the largest payer was Boston Scientific Corporation. The 769 providers of this specialty with any payment received $3,397.95 on average. Payments are reported by manufacturers, not by the provider, and are not a sign of wrongdoing.

  1. Michael Amster$167.50
  2. Specialty average$3,397.95

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. Santa Cruz Community Health CentersSanta Cruz, CA

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

Pain Medicine Physician providers in California

There are 140 pain medicine physician records in California.

Other pain medicine physician records in California

  1. Nathan Abdelsayed, M.DWest Covina, CA1295230142
  2. Rohit Aiyer, M.D.Huntington Beach, CA1801207014
  3. Emile Allen, M.D.Oakland, CA1043546625
  4. Parham Amini, M.D.Northridge, CA1942558556
  5. Kasra Amirdelfan, MDWalnut Creek, CA1033113642
  6. Rasheed Amireh, MDFresno, CA1023040748
  7. Joe ArbourHuntington Beach, CA1649918889
  8. Jeanne Axler, M.D.Santa Monica, CA1083648547
  9. Feng Bai, MDTracy, CA1336108372
  10. Stephen Banister, M.D.Grass Valley, CA1376768416

Common questions

What is Michael A. Amster, MD's NPI number?

Michael A. Amster, MD's National Provider Identifier (NPI) is 1114023058, issued on Sep 16, 2006. An NPI identifies a provider in billing; it is not a license.

Where is Michael A. Amster, MD located?

The NPPES record lists a practice address at 1510 Capitola RD, Santa Cruz, CA, 95062. Phone: (831) 427-3500. Providers update this record themselves, so call before visiting.

How can I verify Michael A. Amster, MD's license?

NPPES lists California license number A81550, 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 Michael A. Amster, MD prescribe under Medicare Part D?

In 2024, Michael A. Amster, MD had 302 Medicare Part D claims for 48 beneficiaries; the average among pain medicine physician prescribers was 2,095. 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.