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

Guillermo J. Giangreco, MD, LLC

Organization Sleep Medicine (Internal Medicine) Physician · NPI 1144501461

Guillermo J. Giangreco, MD, LLC is a Sleep Medicine (Internal Medicine) Physician in Hanover, Maryland. Licensed in Virginia. Registered with an NPI since 2011.

Licensed in
VA
In the registry since
2011
What do these letters mean?
LLC — Limited liability company
A form of business registration, not a clinical qualification.

See every abbreviation used in this directory →

Practice location Address checks out

1741 Allerford Dr
Hanover, MD 21076-1798
Phone: (443) 688-6809
Show map & directions

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

Specialties & licences

Sleep Medicine (Internal Medicine) Physician (primary) Taxonomy 207RS0012X · Licence 0101247753 (VA)

Record details

NPI number1144501461
Entity typeOrganization (Type 2)
Organization subpartNo
Authorized official Guillermo Giangreco — Owner · (443) 688-6809
NPI enumeratedAugust 31, 2011
Last updated in NPPESAugust 31, 2011
Mailing address1741 Allerford Dr, Hanover, MD 21076-1798