Provider records sourced from NPPES (CMS National Plan & Provider Enumeration System). Data current as of October 4, 2026.
NPIDirectory

Mark D Calayag, MD

Individual provider Neurological Surgery Physician · NPI 1336373901

Mark D Calayag, MD is a Neurological Surgery Physician in Orange, California. Practices as a sole proprietor. Licensed in California.

Licensed in
CA
In the registry since
2009
Specialties on file
2
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

200 S Manchester Ave Ste 210
Orange, CA 92868-3217
Phone: (714) 456-6966
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Pin is approximate — placed at the ZIP-code centre, not the exact door.

Specialties & licences

Neurology with Special Qualifications in Child Neurology Physician (primary) Taxonomy 2084N0402X · Licence A137268 (CA)
Neurological Surgery Physician Taxonomy 207T00000X · Licence 137268 (CA)

Record details

NPI number1336373901
Entity typeIndividual (Type 1)
GenderMale
Credentials MD
Sole proprietorYes
NPI enumeratedMay 11, 2009
Last updated in NPPESJanuary 3, 2025
Certification dateJanuary 3, 2025

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 $164 2 payments · 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.

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