Derek A. Barclay, M.D.
Medical Toxicology (Emergency Medicine) Physician · Boston, MA
Derek A. Barclay, M.D. is a medical toxicology (emergency medicine) physician with a practice address in Boston, Massachusetts, and NPI 1801820659, issued on Jul 10, 2006. Check the license (Massachusetts 226628, as entered in NPPES) on the Massachusetts Board of Registration in Medicine; the Medicare figures below come from public CMS files.
- Name
- Derek A. Barclay
- Credential
- M.D.
- Primary taxonomy
- Medical Toxicology (Emergency Medicine) Physician 207PT0002X
- License number
- 226628 MA
Self-reported in NPPES; status is on the state search - Practice location
- Brigham And Women's Hospital, Boston, MA 02115
- Phone
- (617) 732-5656
- Enumerated
- Jul 10, 2006
- Record last updated
- Jul 8, 2007 (not updated in 19 years: call before relying on the address or phone)
- Entity
- Type 1 · individual
4 nearest medical toxicology (emergency medicine) physician records → All 5 in Massachusetts → Look up another NPI →
Also registered at Brigham And Women's Hospital
A shared address usually means a shared clinic or building; it does not show who employs whom.
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- Aiden Feng, MD, MBAAnesthesiology Physician1265888994
- John Finnigan, MD, PHDStudent in an Organized Health Care Education/Training Program1124655121
Verify Derek A. Barclay in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMassachusetts Board of Registration in Medicine
Search for license 226628Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
83% more Medicare Part D claims than the average medical toxicology (emergency medicine) physician in 2024
252 Medicare Part D claims for 190 beneficiaries, against an average of 138 among the 103 providers of this specialty who prescribed in Part D. 46 claims were for opioids.
Most prescribed
- Oxycodone-Acetaminophen39 claims
- Cephalexin36 claims
- Prednisone29 claims
- Ondansetron Odt18 claims
- Doxycycline Monohydrate13 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.
Medical Toxicology (Emergency Medicine) Physician providers in Massachusetts
There are 5 medical toxicology (emergency medicine) physician records in Massachusetts.
All 5 in Massachusetts → Every provider in Boston → Medical Toxicology (Emergency Medicine) Physician nationwide →
The 4 medical toxicology (emergency medicine) physician records with the nearest ZIP codes
- Michele Burns, MDBoston, MA 021151942267133
- Steven Salhanick, MDBoston, MA 021151679582852
- Michael Burns, M.D.Boston, MA 022151801960158
- Katherine Tang, MDBoston, MA 022151154901304
Common questions
What is Derek A. Barclay, M.D.'s NPI number?
Derek A. Barclay, M.D.'s National Provider Identifier (NPI) is 1801820659, issued on Jul 10, 2006. An NPI identifies a provider in billing; it is not a license.
Where is Derek A. Barclay, M.D. located?
The NPPES record lists a practice address at Brigham And Women's Hospital, Boston, MA, 02115. Phone: (617) 732-5656. Providers update this record themselves, so call before visiting.
How can I verify Derek A. Barclay, M.D.'s license?
NPPES lists Massachusetts license number 226628, 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 Derek A. Barclay, M.D. prescribe under Medicare Part D?
In 2024, Derek A. Barclay, M.D. had 252 Medicare Part D claims for 190 beneficiaries; the average among medical toxicology (emergency medicine) physician prescribers was 138. 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.