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

John Mark Demay, MD

Individual provider Dermatology Physician · NPI 1366447294

John Mark Demay, MD is a Dermatology in Sioux City, Iowa. Graduated from University of Nebraska College of Medicine in 1989, 37 years ago. Practices with Dermatology Associates of Siouxland PC, a 3-clinician group and accepts Medicare assignment. Licensed in Iowa.

Years since qualifying
37
Trained at
University of Nebraska College of Medicine
Licensed in
IA
In the registry since
2005
What do these letters mean?
MD — Doctor of Medicine
A physician who completed allopathic medical school.

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Practice location Address checks out

2930 Hamilton Blvd Ste 102
Sioux City, IA 51104-2431
Phone: (712) 277-9370
Fax: (712) 252-4733
Show map & directions

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

Specialties & licences

Dermatology Physician (primary) Taxonomy 207N00000X · Licence 31906 (IA)

Record details

NPI number1366447294
Entity typeIndividual (Type 1)
GenderMale
Credentials MD
Sole proprietorYes
NPI enumeratedJune 16, 2005
Last updated in NPPESAugust 16, 2016
Mailing address2930 Hamilton Blvd, Ste 102, Sioux City, IA 51104-2431

Medicare enrollment

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

Medicare specialtyDERMATOLOGY
Medical schoolUNIVERSITY OF NEBRASKA COLLEGE OF MEDICINE
Graduated 1989 (37 years in practice)
Group practice Dermatology Associates Of Siouxland Pc — 3 clinicians
Accepts Medicare assignment Yes — accepts the Medicare-approved amount

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