Active NPI
John T. Harrison, M.D.
- Internal Medicine Physician
- Baltimore, MD
National Provider Identifier
1770525636
On this page
Key facts
NPPES NPI Registry- Primary specialty
- Internal Medicine Physician
- License
- D0044635
- Practice address
- 2200 Kernan Dr
Baltimore, MD 21207-6665 - Phone
- (410) 448-2500
- NPI assigned
- Jun 12, 2006
- Sex
- Male
- Sole proprietor
- No
NPPES NPI Registry
Registry information is reported by the provider to CMS and is not verified. About this source
Specialties & licenses 1
| Specialty (taxonomy) | Code | License | State | Primary |
|---|---|---|---|---|
| Internal Medicine Physician | 207R00000X | D0044635 | MD | Primary |
Addresses
Primary practice location
2200 Kernan Dr
Baltimore, MD 21207-6665
Mailing address
302 Wyndhurst Ave
Baltimore, MD 21210-2409
Phone (410) 435-4456
Medicare participation
Medicare enrollment files- Medicare fee-for-service enrollment
- Not listed in the public Medicare enrollment file
National Provider Directory
National Provider Directory- Medicare enrollment (NPD)
- Enrolled
- Credentials
- Doctor of Medicine
State licenses
| License | State | Type | Specialty |
|---|---|---|---|
| D0044635 | MD | MD | Internal Medicine Physician |
Practice roles
| Organization | Specialty | Status | New patients |
|---|---|---|---|
| Hospital Physician Services, LLLP | Internal Medicine | Past | Accepting new patients |
| Joseph S. Fastow, M.D., P.a. | Past | Accepting new patients |
Organizations & group practices 2
Organizations this provider is connected to: Medicare benefit reassignments (the organization bills Medicare for this provider’s services), Care Compare group memberships and National Provider Directory roles.
-
- General Acute Care Hospital
- Westminster, MD
- NPI 1457302713
Internal Medicine
-
- Critical Access Hospital
- Prince Frederick, MD
- NPI 1861443103
NPI Registry JSON
The complete NPPES record for this NPI in the NPI Registry API format.
{
"created_epoch": "1150070400000",
"enumeration_type": "NPI-1",
"last_updated_epoch": "1783900800000",
"number": "1770525636",
"addresses": [
{
"country_code": "US",
"country_name": "United States",
"address_purpose": "MAILING",
"address_type": "DOM",
"address_1": "302 WYNDHURST AVE",
"city": "BALTIMORE",
"state": "MD",
"postal_code": "212102409",
"telephone_number": "410-435-4456"
},
{
"country_code": "US",
"country_name": "United States",
"address_purpose": "LOCATION",
"address_type": "DOM",
"address_1": "2200 KERNAN DR",
"city": "BALTIMORE",
"state": "MD",
"postal_code": "212076665",
"telephone_number": "410-448-2500"
}
],
"practiceLocations": [],
"basic": {
"last_name": "HARRISON",
"first_name": "JOHN",
"middle_name": "T.",
"name_prefix": "Dr.",
"credential": "M.D.",
"sole_proprietor": "NO",
"sex": "M",
"enumeration_date": "2006-06-12",
"last_updated": "2026-07-13",
"status": "A"
},
"taxonomies": [
{
"code": "207R00000X",
"taxonomy_group": "",
"desc": "Internal Medicine",
"state": "MD",
"license": "D0044635",
"primary": true
}
],
"identifiers": [],
"endpoints": [],
"other_names": []
}Other providers in Baltimore, MD
Sources for this page
- NPPES NPI Registry (CMS): identity, addresses, specialties, licenses, identifiers and endpoints. Last updated by the provider on Jul 13, 2026; self-reported and not verified by CMS. Specialty names from the NUCC taxonomy.
- National Provider Directory (CMS): practice roles, locations, licenses, networks and endpoints.