John Morrissey, MD
John Morrissey, MD is a Critical Care Medicine (Internal Medicine) Physician in Washington, DC, registered under NPI 1740293984. This provider registers 2 separate taxonomy codes, which usually means they practise across more than one recognised specialty.
Getting there
The practice address on file is 1150 VARNUM ST NE, Washington, DC 20017. We have not yet mapped what surrounds this office — parking, transit, and nearby pharmacies are added as our data collection reaches each location.
Credentials and Medicare
| Licence | State | Specialty |
|---|---|---|
| MD20772 | DC | Critical Care Medicine (Internal… primary |
| MD20772 | DC | Hospitalist Physician |
This provider holds licence MD20772 issued in DC. A licence number in NPPES reflects what was filed at registration — it does not confirm the licence is still active today.
- Status
- Approved
- Provider type
- Practitioner - Pulmonary Disease
- PAC ID
- 5597934422
Enrolled in Medicare 6 times, across 5 states:
| State | Enrollment ID | Provider type |
|---|---|---|
| Maryland | I20110811000150 | Practitioner - Pulmonary Disease |
| District of Columbia | I20111227000480 | Practitioner - Internal Medicine |
| South Carolina | I20200602002781 | Practitioner - Pulmonary Disease |
| Virginia | I20210623000991 | Practitioner - Critical Care (intensivists) |
| South Carolina | I20210819001152 | Practitioner - Critical Care (intensivists) |
| Tennessee | I20251002000369 | Practitioner - Critical Care (intensivists) |
Medicare enrolment is recorded as approved under the provider type Practitioner - Pulmonary Disease. There are 6 separate enrolment records across 5 states (MD, DC, SC, VA, TN). Multiple enrolments usually mean the provider bills Medicare from more than one practice location, or has kept an earlier enrolment after moving. Each record carries its own enrolment ID, listed above. Being enrolled means the provider can bill Medicare; it does not tell you whether they are currently accepting new Medicare patients. Call the office to confirm.
What Critical Care Medicine covers
An internist who diagnoses, treats and supports patients with multiple organ dysfunction. This specialist may have administrative responsibilities for intensive care units and may also facilitate and coordinate patient care among the primary physician, the critical care staff and other specialists. NUCC Health Care Provider Taxonomy, code 207RC0200X
All registered taxonomy codes
This provider registers 2 taxonomy codes. The primary code is what appears on most claims; the others record additional recognised specialties.
| Code | Specialty | Licence | State | |
|---|---|---|---|---|
| 207RC0200X | Critical Care Medicine (Internal Medicine) Physician Critical Care Medicine | MD20772 | DC | primary |
| 208M00000X | Hospitalist Physician | MD20772 | DC |
The taxonomy records how the provider classifies their own practice. It does not confirm which conditions they currently treat, whether they are accepting new patients, or which insurance they take — call the office for that.
Full NPPES record
An NPI-1 identifies a single person. It stays with the clinician for life, even if they move practice or change state, which is why the address on file can lag behind where they actually work today.
| NPI | 1740293984 valid check digit |
|---|---|
| Entity type | Individual (NPI-1) |
| Enumeration date | Aug 15, 2006 |
| Last updated | Jul 29, 2013 |
| Status | Active |
| Sole proprietor | No |
| Credential | MD |
| Practice address |
1150 VARNUM ST NE Washington, DC 20017 (202) 269-7000 |
Number check
How the check works, step by step
Every NPI carries a Luhn check digit — the same scheme used on credit cards. CMS prefixes the number with 80840 before computing it, which marks it as a US health identifier.
| Digit | 8 | 0 | 8 | 4 | 0 | 1 | 7 | 4 | 0 | 2 | 9 | 3 | 9 | 8 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Doubled? | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 |
| Value | 8 | 0 | 8 | 8 | 0 | 2 | 7 | 8 | 0 | 4 | 9 | 6 | 9 | 7 |
Sum = 76 · next multiple of 10 = 80 · check digit = 4 · actual last digit = 4
A valid check digit only means the number is well-formed. It does not mean the provider is licensed, active, or in good standing — those are separate questions answered by the sections above.