Gwendolyn Merchant, CRNP-PMH
Gwendolyn Merchant, CRNP-PMH is a Psychiatric/Mental Health Nurse Practitioner in Crofton, MD, registered under NPI 1578844601. This provider registers 5 separate taxonomy codes, which usually means they practise across more than one recognised specialty.
Getting there
The practice address on file is 1662 VILLAGE GRN STE 100, Crofton, MD 21114. 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 |
|---|---|---|
| R263556 | MD | Psychiatric/Mental Health Nurse… primary |
| RN578488 | PA | Registered Nurse |
| SP011515 | PA | Nurse Practitioner |
| SP011515 | PA | Family Nurse Practitioner |
| SPO27315 | PA | Psychiatric/Mental Health Nurse… |
| SP011515 | PA | Primary Care Nurse Practitioner |
Licences are recorded in 2 states: MD, PA. Providers licensed in several states often practise near a state border or deliver telehealth across state lines.
- Status
- Approved
- Provider type
- Practitioner - Nurse Practitioner
- PAC ID
- 0244476653
Medicare enrolment is recorded as approved under the provider type Practitioner - Nurse Practitioner. This means the provider is enrolled to bill Medicare, though it does not tell you whether they are currently accepting new Medicare patients. Call the office to confirm.
Licensed in 2 states
This provider holds licences in 2 states: Maryland and Pennsylvania. The practice address on file is in Crofton, MD, but a licence in another state usually means they see patients there too — either at a second location or by telehealth. If the address above is far from you, it is worth calling to ask whether they practise closer to where you live.
- Licence
- R263556
- Specialty
- Psychiatric/Mental Health Nurse…
Licence numbers are self-reported to NPPES at registration. They do not confirm a licence is currently active, in good standing, or valid for the specialty shown — only the state board can tell you that, which is why we link to each one.
What Psychiatric/Mental Health covers
Definition to come... NUCC Health Care Provider Taxonomy, code 363LP0808X
All registered taxonomy codes
This provider registers 6 taxonomy codes. The primary code is what appears on most claims; the others record additional recognised specialties.
| Code | Specialty | Licence | State | |
|---|---|---|---|---|
| 363LP0808X | Psychiatric/Mental Health Nurse Practitioner Psychiatric/Mental Health | R263556 | MD | primary |
| 163W00000X | Registered Nurse | RN578488 | PA | |
| 363L00000X | Nurse Practitioner | SP011515 | PA | |
| 363LF0000X | Family Nurse Practitioner Family | SP011515 | PA | |
| 363LP0808X | Psychiatric/Mental Health Nurse Practitioner Psychiatric/Mental Health | SPO27315 | PA | |
| 363LP2300X | Primary Care Nurse Practitioner Primary Care | SP011515 | PA |
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 | 1578844601 valid check digit |
|---|---|
| Entity type | Individual (NPI-1) |
| Enumeration date | Sep 2, 2011 |
| Last updated | Mar 12, 2025 |
| Status | Active |
| Sole proprietor | No |
| Credential | CRNP-PMH |
| Practice address |
1662 VILLAGE GRN STE 100 Crofton, MD 21114 (410) 757-2077 |
| Other identifiers |
232212638
(PA) |
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 | 5 | 7 | 8 | 8 | 4 | 4 | 6 | 0 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Doubled? | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 |
| Value | 8 | 0 | 8 | 8 | 0 | 2 | 5 | 5 | 8 | 7 | 4 | 8 | 6 | 0 |
Sum = 69 · next multiple of 10 = 70 · check digit = 1 · actual last digit = 1
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.