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

William Brian Greiser, MD

Individual provider Emergency Medicine Physician · NPI 1720114408

William Brian Greiser, MD is an Emergency Medicine Physician in Trinidad, Colorado. Licensed in Colorado. Registered with an NPI since 2007.

Licensed in
CO
In the registry since
2007
What do these letters mean?
MD — Doctor of Medicine
A physician who completed allopathic medical school.

See every abbreviation used in this directory →

Practice location Address checks out

410 Benedicta Ave
Trinidad, CO 81082-2005
Phone: (800) 893-9698
Show map & directions

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

Specialties & licences

Emergency Medicine Physician (primary) Taxonomy 207P00000X · Licence 36079 (CO)

Record details

NPI number1720114408
Entity typeIndividual (Type 1)
GenderMale
Credentials MD
Sole proprietorNo
NPI enumeratedFebruary 26, 2007
Last updated in NPPESJuly 8, 2007
Mailing address200 Corporate Blvd, Ste 201, Lafayette, LA 70508-3870

Other providers in Trinidad