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Dr. Johnathon Toma Markus, M.D.

Hospitalist Physician in Clinton Twp, MI · enumerated 2012 · practices at Trillium Anesthesia Services, Pllc.

Data current as of Jul 13, 2026 · sourced from CMS NPPES

National Provider Identifier

1548521461

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Registry record

Entity type Individual (Type 1)
Name Dr. Johnathon Toma Markus
Credential M.D.
Sex Male
Practice address 37399 Garfield Rd Ste 104, Clinton Twp, MI, 48036
Phone (586) 569-3379
Fax (586) 576-6264
Enumeration date Jun 6, 2012
Last updated in NPPES Apr 23, 2019

Taxonomy & licenses

390200000X Student in an Organized Health Care Education/Training Program Student, Health Care Secondary
208M00000X Hospitalist Physician Allopathic & Osteopathic Physicians · License 4301106661 (MI) Primary
MD · Doctor of Medicine: A physician who completed medical school (allopathic medicine), residency training, and state licensure. About the MD credential

What is an NPI number?

A National Provider Identifier (NPI) is a unique 10-digit number that CMS assigns to every U.S. healthcare provider and organization under HIPAA. Type 1 NPIs identify individual providers; Type 2 NPIs identify organizations. The NPI appears on insurance claims, prescriptions, and credentialing paperwork, and never changes, even if the provider moves or changes specialty.

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Frequently asked questions

Is this the official NPI registry?
No. NPI Portal is a private site built on public CMS NPPES data. The official registry is npiregistry.cms.hhs.gov, operated by CMS.
What specialty is Johnathon Markus?
Johnathon Markus is registered in NPPES with the primary taxonomy of Hospitalist Physician. The taxonomy code describes the provider's classification and area of specialization for claims and credentialing.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2019-04-23.