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

John Loh

Individual provider Internal Medicine Physician · NPI 1306852827

John Loh practises Internal Medicine in Baltimore, Maryland. Graduated from Michigan State University College of Human Medicine in 1984, 42 years ago. Practices with Mace Medical LLC, a 15-clinician group, accepts Medicare assignment and offers telehealth. Licensed in Maryland.

Years since qualifying
42
Trained at
Michigan State University College of Human Medicine
Licensed in
MD
In the registry since
2006
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Practice location Address checks out

1124 Mace Ave
Baltimore, MD 21221-3315 Not confirmed with CMS for 19 years — call before visiting
Phone: (410) 391-6996
Fax: (410) 687-6877
Show map & directions

Directions in Google Maps · Apple Maps · OpenStreetMap

Pin is approximate — placed at the ZIP-code centre, not the exact door.

Specialties & licences

Internal Medicine Physician (primary) Taxonomy 207R00000X · Licence H0035593 (MD)

Record details

NPI number1306852827
Entity typeIndividual (Type 1)
GenderMale
Sole proprietorYes
NPI enumeratedAugust 1, 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 schoolMICHIGAN STATE UNIVERSITY COLLEGE OF HUMAN MEDICINE
Graduated 1984 (42 years in practice)
Group practice Mace Medical Llc — 15 clinicians
Accepts Medicare assignment Yes — accepts the Medicare-approved amount
TelehealthOffers telehealth services

Procedures

From CMS Care Compare, which counts the procedures a clinician billed to Original Medicare and Medicare Advantage over a recent 12-month period. CMS reports a fixed list of common procedures, so this is not everything the clinician does. Counts of 10 or fewer are given as a range, because CMS withholds small numbers.

Removal of skin lesions 1–10 times
Removal or shaving of skin growth 1–10 times

The percentile compares how often this clinician performed the procedure with other clinicians who performed it, as CMS calculates it. It measures volume, not outcomes or skill.

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 patients366
Services billed 2,285 a service is one billed item, such as a visit, a test or a procedure
Average patient age74

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 $1,959 104 payments · 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.

Colleagues at Mace Medical LLC

Clinicians the CMS Doctors & Clinicians file lists under the same group practice. CMS counts 15 clinicians in the practice; 12 are shown here.

Other providers in Baltimore