Provider records sourced from NPPES (CMS National Plan & Provider Enumeration System). Data current as of October 4, 2026.
NPIDirectory

Dr. Carl Johnson, MD

Individual provider Internal Medicine Physician · NPI 1205994266

Dr. Carl Johnson, MD practises Internal Medicine in Largo, Maryland. Graduated from George Washington University School of Medicine in 1991, 35 years ago. Practices with Medstar Medical Group II LLC, a 3,717-clinician group, accepts Medicare assignment and offers telehealth. Licensed in Maryland.

Years since qualifying
35
Trained at
George Washington University School of Medicine
Licensed in
MD
In the registry since
2006
What do these letters mean?
MD — Doctor of Medicine
A physician who completed allopathic medical school.

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Practice location Address checks out

1221 Mercantile Ln
Largo, MD 20774-5374 Not confirmed with CMS for 19 years — call before visiting
Phone: (301) 618-5540
Fax: (301) 618-5525
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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 D45881 (MD)

Record details

NPI number1205994266
Entity typeIndividual (Type 1)
GenderMale
Credentials MD
Sole proprietorNo
NPI enumeratedDecember 4, 2006
Last updated in NPPESJuly 8, 2007

Medicare enrollment

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

Medicare specialtyINTERNAL MEDICINE
Medical schoolGEORGE WASHINGTON UNIVERSITY SCHOOL OF MEDICINE
Graduated 1991 (35 years in practice)
Group practice Medstar Medical Group Ii Llc — 3717 clinicians
Accepts Medicare assignment Yes — accepts the Medicare-approved amount
TelehealthOffers telehealth services
Practice locations3 on file with Medicare

Medicare patients and services, 2024

From the CMS Medicare Physician & Other Practitioners file for calendar year 2024. It counts Original Medicare patients only, so a practice that mostly sees Medicare Advantage or privately insured patients looks smaller here than it is.

Medicare patients463
Services billed 1,526 a service is one billed item, such as a visit, a test or a procedure
Average patient age75

Dollar amounts are not shown. What Medicare pays a practice is gross billings, before staff, premises and tax and including the cost of any drugs it administers, so it is not what a clinician earns.

Payments from drug and device companies, 2025

Drug and device makers are required by federal law (the Physician Payments Sunshine Act) to report what they pay or give to clinicians, and CMS publishes the reports as Open Payments. This is the 2025 program year. A report is a record of a payment, not an allegation of anything, and many are small items such as meals. Only general payments are listed here; research payments and ownership or investment interests are reported separately by CMS and are not shown.

Food and Beverage $16 1 payment · a meal or drink at a meeting or visit, not a fee

Each amount is the sum of what companies reported for that kind of payment in 2025, rounded to the dollar. Not all of it is income to the clinician: a meal is not a fee, a charitable contribution goes to a charity, and a royalty or an acquisition payment is not a salary.

Check a report, or dispute one, at the source in CMS’s own tool, Open Payments. Corrections go through CMS’s dispute process. This site removes a home address on request and asks for no proof, because that is privacy; it will not remove an accurate payment report on request, because that is a statutory public disclosure.

Practises at

Facilities the CMS Facility Affiliation file lists for this clinician. Those with a page here are linked.

  • Medstar Washington Hospital Center Hospital · Washington, DC · listed as Washington Hospital Center Corporation
  • Amedisys Home Health Care Home health agency · Largo, MD
  • Americare In Home Nursing Home health agency · Fort Washington, MD
  • Medstar Health Home Care Home health agency · Hyattsville, MD

Colleagues at Medstar Medical Group II LLC

Clinicians the CMS Doctors & Clinicians file lists under the same group practice. CMS counts 3717 clinicians in the practice; 12 are shown here.

Other providers in Largo