Registry data as of Aug 27, 2026

Selwyn Mahon, M.D.

Emergency Medicine Physician · Tamuning, GU

Selwyn Mahon, M.D. is an emergency medicine physician with a practice address in Tamuning, Guam, and NPI 1992816169, issued on Aug 31, 2006. Check the license with the Guam board that licenses this profession; the Medicare figures below come from public CMS files.

Record from CMS NPPES, loaded Aug 27, 2026 · Medicare files 2023 and 2024 · method · Verify with CMS →

NPPES recordas of Aug 27, 2026
1992816169
Name
Selwyn Mahon
Credential
M.D.
Primary taxonomy
Emergency Medicine Physician 207P00000X
Practice location
850 Gov. Carlos Camacho Road, Tamuning, GU 96913
Phone
(671) 647-2350
Enumerated
Aug 31, 2006
Entity
Type 1 · individual
Public record from CMS NPPES (open it on the CMS NPI Registry). A record is not a license: verify it with the state board.
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Also registered at 850 Gov. Carlos Camacho Road

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

  1. Reynald Lim, M.D.Anesthesiology Physician1679549869
  2. Kristy Joy Mary, RDN, LDRegistered Dietitian1255981502

Verify Selwyn Mahon in five checks

  1. 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
  2. 2LicenseActive license and public ordersWhich Guam board licenses this professionCheck 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
Find the Guam license search

PlainDoctor does not match the HHS-OIG exclusion list to individual records: most entries carry no NPI. Search the OIG exclusion list by name.

76% fewer Medicare Part D claims than the average emergency medicine physician in 2024

86 Medicare Part D claims for 60 beneficiaries, against an average of 355 among the 49,029 providers of this specialty who prescribed in Part D.

  1. Selwyn Mahon86
  2. Specialty average355

Most prescribed

  1. Prednisone13 claims
  2. Cephalexin11 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.

One hospital or facility affiliation

  1. East Harbor Partners PCAlexandria, VA

Source: CMS Doctors and Clinicians affiliations; Hospital General Information (Care Compare) (data.cms.gov). Star ratings are CMS hospital ratings, not ratings of this provider.

5 emergency medicine physician records list a Tamuning practice address

They are 5 of the 411 NPPES records with a Tamuning practice address, and 23 emergency medicine physician records in Guam.

Other emergency medicine physician records in Guam

  1. Jessica ArrottAgana Heights, GU1902365737
  2. Thomas Baugh, D.O.Agana Heights, GU1255302485
  3. Anthony Bekkerman, M.D.Dededo, GU1164522819
  4. Christopher Chisholm, MDAgana Heights, GU1407836075
  5. Taylor Desrosiers, MD, MBAAgana Heights, GU1205176773
  6. Eric Greenfield, D.OTamuning, GU1457558025
  7. Kathryn Guffrey, M.D.Dededo, GU1144512252
  8. John Haggerty, D.O.Agana Heights, GU1427395326
  9. Sarah Haley-Wien, D.O.Dededo, GU1538242292
  10. Brian Harris, M.D.Dededo, GU1982611950

Common questions

What is Selwyn Mahon, M.D.'s NPI number?

Selwyn Mahon, M.D.'s National Provider Identifier (NPI) is 1992816169, issued on Aug 31, 2006. An NPI identifies a provider in billing; it is not a license.

Where is Selwyn Mahon, M.D. located?

The NPPES record lists a practice address at 850 Gov. Carlos Camacho Road, Tamuning, GU, 96913. Phone: (671) 647-2350. Providers update this record themselves, so call before visiting.

How can I verify Selwyn Mahon, M.D.'s license?

Search the Guam board that licenses this profession; the NPPES record confirms identity only.

How much does Selwyn Mahon, M.D. prescribe under Medicare Part D?

In 2024, Selwyn Mahon, M.D. had 86 Medicare Part D claims for 60 beneficiaries; the average among emergency medicine physician prescribers was 355. Part D covers Medicare prescriptions only.

Source: CMS National Plan and Provider Enumeration System (NPPES), loaded Aug 27, 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.

Every figure on PlainDoctor is rendered directly from the federal CMS NPPES registry, Medicare Part D, MIPS, and Open Payments records, no number is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of Aug 27, 2026.