NPPES file of Aug 9, 2026

Jason John Gass, D.O.

Internal Medicine Physician · Saint Louis, MO

Jason John Gass, D.O. is an internal medicine physician with a practice address in Saint Louis, Missouri, and NPI 1700224201, issued on Jun 6, 2013. Check the license (Missouri 2018022314, as entered in NPPES) on the Missouri Board of Registration for the Healing Arts; 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
1700224201
Name
Jason John Gass
Credential
D.O.
Primary taxonomy
Internal Medicine Physician 207R00000X
License numbers
2018022314 MO
DO-04881 IA
Self-reported in NPPES; status is on the state search
Practice location
621 S New Ballas RD Ste 7018B, Saint Louis, MO 63141
Phone
(314) 251-4949
Enumerated
Jun 6, 2013
Record last updated
Sep 4, 2018 (not updated in 8 years: call before relying on the address or phone)
Fax
(314) 251-4368
Medicare enrollment
Enrolled (PECOS I20181006000244); 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 621 S New Ballas RD Ste 7018B

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

  1. Frederick Kuhlmann, MDInfectious Disease Physician1417981481
  2. Hamzah Mohd, M.D.,Infectious Disease Physician1952559320

Verify Jason John Gass in five checks

  1. 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
  2. 2LicenseActive license and public ordersMissouri Board of Registration for the Healing Arts
    Search for license 2018022314
    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 Missouri license search

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74% fewer Medicare Part D claims than the average internal medicine physician in 2024

838 Medicare Part D claims for 138 beneficiaries, against an average of 3,176 among the 108,855 providers of this specialty who prescribed in Part D. Brand-name drugs were 11% of claims.

  1. Jason Gass838
  2. Specialty average3,176

Most prescribed

  1. Ceftriaxone78 claims
  2. Doxycycline Hyclate77 claims
  3. Vancomycin Hcl56 claims
  4. Cefadroxil53 claims
  5. Azithromycin52 claims
  6. Tobramycin Sulfate48 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: $320.05

17 payments; by number, the most common kind was food and beverage; the largest payer was Gilead Sciences, Inc. The 50,334 providers of this specialty with any payment received $1,303.06 on average. Payments are reported by manufacturers, not by the provider, and are not a sign of wrongdoing.

  1. Jason Gass$320.05
  2. Specialty average$1,303.06

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. Mercy Clinic Infectious Disease LLCSaint Louis, MO

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

Jason John Gass among 2,604 internal medicine physician records in Missouri

Jason John Gass, D.O. is one of 2,604 internal medicine physician records with a practice address in Missouri. 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 2013, is newer than 58% of them.

  • NPI issued2013 · 58% of these records are older, 40% newer
  • In a Medicare fileYes · 77% of these records are
  • In the CMS Doctors and Clinicians fileYes · 55% of these records are
  • Graduated2013 · median 2006 among the 1,443 with a school on file
  • Record last updated2018 · 48% of these records were not updated in five years or more

Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207R00000X and a Missouri practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).

941 internal medicine physician records list a practice address in Saint Louis

They are 941 of the 27,605 NPPES records with a practice address in Saint Louis, and 2,604 internal medicine physician records in Missouri.

The 8 internal medicine physician records with the nearest ZIP codes

  1. Daniel Bauer, MDSaint Louis, MO 631411144222506
  2. Michele Bellamy, MDCreve Coeur, MO 631411134194863
  3. Shobha Dixit, MDSaint Louis, MO 631411902871650
  4. Carolyn Koenig, MDSaint Louis, MO 631411063488278
  5. Bernard McGuire, M.D.Saint Louis, MO 631411942274030
  6. Angela Miller, M.D.Saint Louis, MO 631411184605883
  7. C Molden, MDSaint Louis, MO 631411720086747
  8. Margaret Murphy, M.D.Saint Louis, MO 631411043285745

Common questions

What is Jason John Gass, D.O.'s NPI number?

Jason John Gass, D.O.'s National Provider Identifier (NPI) is 1700224201, issued on Jun 6, 2013. An NPI identifies a provider in billing; it is not a license.

Where is Jason John Gass, D.O. located?

The NPPES record lists a practice address at 621 S New Ballas RD Ste 7018B, Saint Louis, MO, 63141. Phone: (314) 251-4949. Providers update this record themselves, so call before visiting.

How can I verify Jason John Gass, D.O.'s license?

NPPES lists Missouri license number 2018022314, as entered by the provider. Search the Missouri Board of Registration for the Healing Arts at https://www.fsmb.org/contact-a-state-medical-board/. The NPPES record confirms identity only; the state search shows license status, expiration and public orders.

How much does Jason John Gass, D.O. prescribe under Medicare Part D?

In 2024, Jason John Gass, D.O. had 838 Medicare Part D claims for 138 beneficiaries; the average among internal medicine physician prescribers was 3,176. 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.