Provider records sourced from NPPES (CMS National Plan & Provider Enumeration System). Data current as of August 10, 2026.
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Mary Maybell Schuessler, RN, FNP-C

Individual provider Medical-Surgical Registered Nurse · NPI 1154131548

Mary Maybell Schuessler, RN, FNP-C is a Nurse Practitioner in Johns Island, South Carolina. Qualified in 2024, 2 years ago. Practices with Onsite Mental Health, a 15-clinician group, works from 2 locations and accepts Medicare assignment. Licensed in South Carolina.

Years since qualifying
2
Licensed in
SC
In the registry since
2025
Specialties on file
2
What do these letters mean?
RN — Registered Nurse
A licensed nurse who completed a nursing degree and passed the NCLEX-RN examination.
FNP-C — Family Nurse Practitioner, Certified
A family nurse practitioner certified by the AANP.

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Practice location Address checks out

3647 Maybank Hwy
Johns Island, SC 29455-4825
Phone: (404) 877-8189
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Pin is approximate — placed at the ZIP-code centre, not the exact door.

Additional practice locations (1)

  • 171 Ashley Ave, Charleston, SC 29425-8908 — (843) 792-1414

Specialties & licences

Primary Care Nurse Practitioner (primary) Taxonomy 363LP2300X · Licence 29480 (SC)
Medical-Surgical Registered Nurse Taxonomy 163WM0705X · Licence RN.279595 (SC)

Record details

NPI number1154131548
Entity typeIndividual (Type 1)
GenderFemale
Credentials RN , FNP-C
Sole proprietorNo
NPI enumeratedJanuary 8, 2025
Last updated in NPPESMay 1, 2025
Certification dateMay 1, 2025

Medicare enrollment

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

Medicare specialtyNURSE PRACTITIONER
Medical schoolOTHER
Graduated 2024 (2 years in practice)
Group practice Onsite Mental Health — 15 clinicians
Accepts Medicare assignment Yes — accepts the Medicare-approved amount
Practice locations2 on file with Medicare

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 $25 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.

Colleagues at Onsite Mental Health

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 Johns Island