Provider records sourced from NPPES (CMS National Plan & Provider Enumeration System). Data current as of August 10, 2026.
NPIDirectory

Jason John Gass, DO

Individual provider Internal Medicine Physician · NPI 1700224201

Jason John Gass, DO is an Infectious Disease in Saint Louis, Missouri. Qualified in 2013, 13 years ago. Practices with Mercy Clinic Infectious Disease LLC, a 4-clinician group, accepts Medicare assignment and offers telehealth. Licensed in Iowa and Missouri.

Years since qualifying
13
Licensed in
IA, MO
In the registry since
2013
Specialties on file
2
What do these letters mean?
DO — Doctor of Osteopathic Medicine
A fully licensed physician, trained like an MD with additional musculoskeletal training. Equivalent practice rights in all 50 states.

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Practice location Address checks out

621 S New Ballas Rd Ste 7018B
Saint Louis, MO 63141
Phone: (314) 251-4949
Fax: (314) 251-4368
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Pin is approximate — placed at the ZIP-code centre, not the exact door.

Specialties & licences

Internal Medicine Physician (primary) Taxonomy 207R00000X · Licence 2018022314 (MO)
Internal Medicine Physician Taxonomy 207R00000X · Licence DO-04881 (IA)

Record details

NPI number1700224201
Entity typeIndividual (Type 1)
GenderMale
Credentials DO
Sole proprietorNo
NPI enumeratedJune 6, 2013
Last updated in NPPESSeptember 4, 2018

Medicare enrollment

From the CMS Doctors & Clinicians file — this clinician is enrolled in Medicare.

Medicare specialtyINFECTIOUS DISEASE
Also practisesINTERNAL MEDICINE
Medical schoolOTHER
Graduated 2013 (13 years in practice)
Group practice Mercy Clinic Infectious Disease Llc — 4 clinicians
Accepts Medicare assignment Yes — accepts the Medicare-approved amount
TelehealthOffers telehealth services

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