NPPES file of Aug 9, 2026

Margaret Hollister Sigman

Allergy & Immunology Physician · Midlothian, VA

Margaret Hollister Sigman is an allergy & immunology physician with a practice address in Midlothian, Virginia, and NPI 1447461108, issued on May 24, 2007. Check the license (Virginia 0101253799, as entered in NPPES) on the Virginia Department of Health Professions; 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
1447461108
Name
Margaret Hollister Sigman
Primary taxonomy
Allergy & Immunology Physician 207K00000X
License numbers
0101253799 VA
200801988 NC
Self-reported in NPPES; status is on the state search
Practice location
5924 Harbour Park Dr, Midlothian, VA 23112
Phone
(804) 739-9005
Enumerated
May 24, 2007
Record last updated
Mar 10, 2017 (not updated in 9 years: call before relying on the address or phone)
Fax
(804) 739-9006
Medicaid IDs
21474 LA
5910944 NC
Medicare enrollment
Enrolled (PECOS I20131014000986); accepts Medicare assignment
Telehealth
Offers telehealth (CMS)
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 5924 Harbour Park Dr

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

  1. Barry Feinstein, M.D.Allergy & Immunology Physician1023095411

Verify Margaret Hollister Sigman in five checks

  1. 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
  2. 2LicenseActive license and public ordersVirginia Department of Health Professions
    Search for license 0101253799
    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 Virginia license search

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48% more Medicare Part D claims than the average allergy & immunology physician in 2024

1,093 Medicare Part D claims for 160 beneficiaries, against an average of 741 among the 2,899 providers of this specialty who prescribed in Part D. Brand-name drugs were 22% of claims.

  1. Margaret Sigman1,093
  2. Specialty average741

Most prescribed

  1. Montelukast Sodium205 claims
  2. Azelastine Hcl146 claims
  3. Fluticasone Propionate97 claims
  4. Levocetirizine Dihydrochloride91 claims
  5. Trelegy Ellipta72 claims
  6. Albuterol Sulfate Hfa65 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: $2,394.33

119 payments; by number, the most common kind was food and beverage; the largest payer was Regeneron Healthcare Solutions, Inc. The 2,496 providers of this specialty with any payment received $8,321.81 on average. Payments are reported by manufacturers, not by the provider, and are not a sign of wrongdoing.

  1. Margaret Sigman$2,394.33
  2. Specialty average$8,321.81

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. Advanced Allergy And Asthma OF VirginiaMidlothian, VA

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

Margaret Hollister Sigman among 136 allergy & immunology physician records in Virginia

Margaret Hollister Sigman is one of 136 allergy & immunology physician records with a practice address in Virginia. 87% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2007, is newer than 53% of them.

  • NPI issued2007 · 53% of these records are older, 35% newer
  • In a Medicare fileYes · 87% of these records are
  • In the CMS Doctors and Clinicians fileYes · 71% of these records are
  • Graduated2003 · median 2002 among the 97 with a school on file
  • Record last updated2017 · 43% of these records were not updated in five years or more

Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207K00000X and a Virginia practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).

Allergy & Immunology Physician providers in Virginia

There are 136 allergy & immunology physician records in Virginia.

The 8 allergy & immunology physician records with the nearest ZIP codes

  1. Barry Feinstein, M.D.Midlothian, VA 231121023095411
  2. Joseph Vilseck, MDMidlothian, VA 231131790762235
  3. Joan Brauckmann, MDWilliamsburg, VA 231851376585240
  4. Robert Brooks, MDWilliamsburg, VA 231851275034449
  5. Timothy Campbell, M.D.Williamsburg, VA 231851891923074
  6. Eric Karlin, M.D.Williamsburg, VA 231851356579486
  7. Stephen Shield, M.D.Williamsburg, VA 231851073590071
  8. Jeremy Brozyna, MDRichmond, VA 232191053920819

Common questions

What is Margaret Hollister Sigman's NPI number?

Margaret Hollister Sigman's National Provider Identifier (NPI) is 1447461108, issued on May 24, 2007. An NPI identifies a provider in billing; it is not a license.

Where is Margaret Hollister Sigman located?

The NPPES record lists a practice address at 5924 Harbour Park Dr, Midlothian, VA, 23112. Phone: (804) 739-9005. Providers update this record themselves, so call before visiting.

How can I verify Margaret Hollister Sigman's license?

NPPES lists Virginia license number 0101253799, as entered by the provider. Search the Virginia Department of Health Professions at https://dhp.virginiainteractive.org/lookup/index. The NPPES record confirms identity only; the state search shows license status, expiration and public orders.

How much does Margaret Hollister Sigman prescribe under Medicare Part D?

In 2024, Margaret Hollister Sigman had 1,093 Medicare Part D claims for 160 beneficiaries; the average among allergy & immunology physician prescribers was 741. 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.