Masaru Ishii, M.D.,PH.D.
Otolaryngology Physician · Baltimore, MD
Masaru Ishii, M.D.,PH.D. is an otolaryngology physician with a practice address in Baltimore, Maryland, and NPI 1427004381, issued on May 25, 2006. Check the license (Maryland D59315, as entered in NPPES) on the Maryland Board of Physicians; the Medicare figures below come from public CMS files.
- Name
- Masaru Ishii
- Credential
- M.D.,PH.D.
- Primary taxonomy
- Otolaryngology Physician 207Y00000X
- License number
- D59315 MD
Self-reported in NPPES; status is on the state search - Practice location
- 4940 Eastern Ave, Baltimore, MD 21224
- Phone
- (410) 550-2368
- Enumerated
- May 25, 2006
- Record last updated
- Feb 8, 2013 (not updated in 13 years: call before relying on the address or phone)
- Medicaid ID
- 384050600 MD
- Medicare enrollment
- Enrolled (PECOS I20100729000643); may accept Medicare assignment
- Medical or professional school
- Perelman School Of Med At The University Of Pennsylvania, 1997
- Entity
- Type 1 · individual
8 nearest otolaryngology physician records → All 257 in Maryland → Look up another NPI →
Also registered at 4940 Eastern Ave
A shared address usually means a shared clinic or building; it does not show who employs whom.
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- Anas AbdullahStudent in an Organized Health Care Education/Training Program1184040917
- Asma Abeer, PA-CMedical Physician Assistant1386356442
- Mona Abraham, MDStudent in an Organized Health Care Education/Training Program1245807395
- Sherifatu Abu, MDInternal Medicine Physician1093372922
Verify Masaru Ishii in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMaryland Board of Physicians
Search for license D59315Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
25% fewer Medicare Part D claims than the average otolaryngology physician in 2024
406 Medicare Part D claims for 105 beneficiaries, against an average of 541 among the 8,339 providers of this specialty who prescribed in Part D.
Most prescribed
- Fluticasone Propionate74 claims
- Azelastine Hcl69 claims
- Ipratropium Bromide60 claims
- Famotidine34 claims
- Prednisone34 claims
- Doxycycline Monohydrate33 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.
The practice group's MIPS final score for 2023 (Medicare payment program): 74.4 of 100
The Merit-based Incentive Payment System score is reported for the practice group, not for one clinician alone. Four categories are weighted into the final score; the average among 454,083 clinicians with a measured score was 83.5.
Source: CMS Quality Payment Program, MIPS performance year 2023, group reporting; category weights for 2023 (qpp.cms.gov).
Bills Medicare through one group practice
- Johns Hopkins UniversityBaltimore, MD
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
Masaru Ishii among 257 otolaryngology physician records in Maryland
Masaru Ishii, M.D.,PH.D. is one of 257 otolaryngology physician records with a practice address in Maryland. 77% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2006, is newer than 14% of them.
- NPI issued2006 · 14% of these records are older, 48% newer
- In a Medicare fileYes · 77% of these records are
- In the CMS Doctors and Clinicians fileYes · 65% of these records are
- Graduated1997 · median 2004 among the 166 with a school on file
- Record last updated2013 · 60% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207Y00000X and a Maryland practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
Otolaryngology Physician providers in Maryland
There are 257 otolaryngology physician records in Maryland.
All 257 in Maryland → Every provider in Baltimore → Otolaryngology Physician nationwide →
The 8 otolaryngology physician records with the nearest ZIP codes
- Carolyn Jenks, MDBaltimore, MD 212241326387564
- Matthew Kashima, M.D.Baltimore, MD 212241487601662
- Jean Kim, M.D.Baltimore, MD 212241386685972
- Christina Navin, CRNPBaltimore, MD 212241154781136
- Obinna NwosuBaltimore, MD 212241235718685
- Choon Park, M.D.Baltimore, MD 212241235179318
- Lazaro Peraza, MDBaltimore, MD 212241164003208
- Rishi SureshBaltimore, MD 212241205413242
Common questions
What is Masaru Ishii, M.D.,PH.D.'s NPI number?
Masaru Ishii, M.D.,PH.D.'s National Provider Identifier (NPI) is 1427004381, issued on May 25, 2006. An NPI identifies a provider in billing; it is not a license.
Where is Masaru Ishii, M.D.,PH.D. located?
The NPPES record lists a practice address at 4940 Eastern Ave, Baltimore, MD, 21224. Phone: (410) 550-2368. Providers update this record themselves, so call before visiting.
How can I verify Masaru Ishii, M.D.,PH.D.'s license?
NPPES lists Maryland license number D59315, as entered by the provider. Search the Maryland Board of Physicians at https://www.mbp.state.md.us/. The NPPES record confirms identity only; the state search shows license status, expiration and public orders.
How much does Masaru Ishii, M.D.,PH.D. prescribe under Medicare Part D?
In 2024, Masaru Ishii, M.D.,PH.D. had 406 Medicare Part D claims for 105 beneficiaries; the average among otolaryngology physician prescribers was 541. Part D covers Medicare prescriptions only.
What is Masaru Ishii, M.D.,PH.D.'s MIPS final score?
The 2023 MIPS final score is 74.4 of 100, reported for the practice group. The average among 454,083 clinicians with a measured score was 83.5.
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.