William G. Tsiaras, M.D., PH.D.
Dermatology Physician · Boston, MA
William G. Tsiaras, M.D., PH.D. is a dermatology physician with a practice address in Boston, Massachusetts, and NPI 1215255526, issued on May 11, 2010. Check the license (Massachusetts 259741, as entered in NPPES) on the Massachusetts Board of Registration in Medicine; the Medicare figures below come from public CMS files.
- Name
- William G. Tsiaras
- Credential
- M.D., PH.D.
- Primary taxonomy
- Dermatology Physician 207N00000X
- License numbers
- 259741 MA
247360 MA
LP01895 RI
Self-reported in NPPES; status is on the state search - Practice location
- 221 Longwood Ave, Boston, MA 02115
- Phone
- (617) 732-4918
- Enumerated
- May 11, 2010
- Record last updated
- Mar 19, 2015 (not updated in 11 years: call before relying on the address or phone)
- Fax
- (617) 582-6060
- Medicare enrollment
- Enrolled (PECOS I20141024000501); accepts Medicare assignment
- Telehealth
- Offers telehealth (CMS)
- Entity
- Type 1 · individual
8 nearest dermatology physician records → All 627 in Massachusetts → Look up another NPI →
Also registered at 221 Longwood Ave
A shared address usually means a shared clinic or building; it does not show who employs whom.
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- Abby Altman, PHDCounseling Psychologist1518220433
Verify William G. Tsiaras in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMassachusetts Board of Registration in Medicine
Search for license 259741Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
7% more Medicare Part D claims than the average dermatology physician in 2024
849 Medicare Part D claims for 166 beneficiaries, against an average of 797 among the 12,802 providers of this specialty who prescribed in Part D. Brand-name drugs were 19% of claims. 12 claims were for opioids.
Most prescribed
- Clobetasol Propionate76 claims
- Triamcinolone Acetonide72 claims
- Ketoconazole71 claims
- Pentoxifylline35 claims
- Lidocaine33 claims
- Mupirocin33 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.
Bills Medicare through one group practice
- Brigham And Womens Physicians Organization IncBoston, MA
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
William G. Tsiaras among 627 dermatology physician records in Massachusetts
William G. Tsiaras, M.D., PH.D. is one of 627 dermatology physician records with a practice address in Massachusetts. 83% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2010, is newer than 56% of them.
- NPI issued2010 · 56% of these records are older, 41% newer
- In a Medicare fileYes · 83% of these records are
- In the CMS Doctors and Clinicians fileYes · 71% of these records are
- Graduated2010 · median 2008 among the 445 with a school on file
- Record last updated2015 · 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 207N00000X and a Massachusetts practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
Dermatology Physician providers in Massachusetts
There are 627 dermatology physician records in Massachusetts.
All 627 in Massachusetts → Every provider in Boston → Dermatology Physician nationwide →
The 8 dermatology physician records with the nearest ZIP codes
- Niroshana Anandasabapathy, MD PHDBoston, MA 021151316145717
- Susan Burgin, M.D.Boston, MA 021151174580906
- Elizabeth Buzney, MDBoston, MA 021151881720621
- Lynda Chin, M.D.Boston, MA 021151437210143
- Caroline Kim, M.D.Boston, MA 021151386602753
- Kubinne Kim, MDBoston, MA 021151437341401
- Thomas Kupper, MDBoston, MA 021151548227945
- Vincent Li, MDBoston, MA 021151427093624
Common questions
What is William G. Tsiaras, M.D., PH.D.'s NPI number?
William G. Tsiaras, M.D., PH.D.'s National Provider Identifier (NPI) is 1215255526, issued on May 11, 2010. An NPI identifies a provider in billing; it is not a license.
Where is William G. Tsiaras, M.D., PH.D. located?
The NPPES record lists a practice address at 221 Longwood Ave, Boston, MA, 02115. Phone: (617) 732-4918. Providers update this record themselves, so call before visiting.
How can I verify William G. Tsiaras, M.D., PH.D.'s license?
NPPES lists Massachusetts license number 259741, as entered by the provider. Search the Massachusetts Board of Registration in Medicine at https://findmydoctor.mass.gov/. The NPPES record confirms identity only; the state search shows license status, expiration and public orders.
How much does William G. Tsiaras, M.D., PH.D. prescribe under Medicare Part D?
In 2024, William G. Tsiaras, M.D., PH.D. had 849 Medicare Part D claims for 166 beneficiaries; the average among dermatology physician prescribers was 797. 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.