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

Alyssa Y Castillo, MD

Individual provider Internal Medicine Physician · NPI 1659752152

Alyssa Y Castillo, MD is registered under Infectious Disease in Aurora, Colorado. Graduated from University of Colorado School of Medicine, Aurora in 2015, 11 years ago. Practices with University Physicians Incorporated, a 3,148-clinician group, works from 2 locations and accepts Medicare assignment. Licensed in Colorado and Massachusetts.

Years since qualifying
11
Trained at
University of Colorado School of Medicine, Aurora
Licensed in
CO, MA
In the registry since
2015
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

1635 Aurora Ct Fl 7
Aurora, CO 80045-2541
Phone: (720) 848-0000
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Pin is approximate — placed at the ZIP-code centre, not the exact door.

Additional practice locations (1)

  • Massachusetts General Hospital, Boston, MA 02114 — (617) 726-7930

Specialties & licences

Infectious Disease Physician (primary) Taxonomy 207RI0200X · Licence DR.0068993 (CO)
Internal Medicine Physician Taxonomy 207R00000X · Licence L-263365 (MA)

Record details

NPI number1659752152
Entity typeIndividual (Type 1)
GenderFemale
Credentials MD
Sole proprietorNo
NPI enumeratedJune 11, 2015
Last updated in NPPESMay 29, 2025
Certification dateMay 29, 2025

Medicare enrollment

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

Medicare specialtyINFECTIOUS DISEASE
Also practisesINTERNAL MEDICINE
Medical schoolUNIVERSITY OF COLORADO SCHOOL OF MEDICINE, AURORA
Graduated 2015 (11 years in practice)
Group practice University Physicians Incorporated — 3148 clinicians
Accepts Medicare assignment Yes — accepts the Medicare-approved amount

Medicare patients and services, 2024

From the CMS Medicare Physician & Other Practitioners file for calendar year 2024. It counts Original Medicare patients only, so a practice that mostly sees Medicare Advantage or privately insured patients looks smaller here than it is.

Medicare patients77
Services billed 231 a service is one billed item, such as a visit, a test or a procedure
Average patient age69

Dollar amounts are not shown. What Medicare pays a practice is gross billings, before staff, premises and tax and including the cost of any drugs it administers, so it is not what a clinician earns.

Practises at

Facilities the CMS Facility Affiliation file lists for this clinician.

Colleagues at University Physicians Incorporated

Clinicians the CMS Doctors & Clinicians file lists under the same group practice. CMS counts 3148 clinicians in the practice; 12 are shown here.

Other providers in Aurora