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Internal Medicine

Maria D. Encarnacion Siaca, MD

Sees patients in Fajardo, PR · Puerto Rico

Summary

Dr. Maria D. Encarnacion Siaca, MD is an internal medicine doctor at 104 Calle Diego Zalduondo, Fajardo, PR 00738. Phone: (787) 863-7580. Accepts Medicare assignment. In 2024, Maria D. Encarnacion Siaca had 22 Original Medicare patients and 84 services. NPI 1750353017. Source: CMS National Downloadable File, updated October 2, 2026; CMS Medicare Physician & Other Practitioners, data year 2024.

  • Specialty: Internal medicine doctor (Medicare lists Internal Medicine)
  • Address: 104 Calle Diego Zalduondo, Fajardo, PR 00738 · Directions (1 more location)
  • Phone: (787) 863‑7580
  • Medicare: Accepts Medicare assignment
  • Medical school: University Central Del Caribe Escuela De Medicina · graduated 1994 (32 years since medical school)
  • Gender (as listed): Female

From official Medicare data

This page shows what Medicare's official clinician data says about Maria D. Encarnacion Siaca, joined by NPI number (data updated October 2, 2026). It is not a recommendation or a rating. Call the office or hospital to confirm before you go.

In a medical emergency, call 911.

Quick answers

Does Maria D. Encarnacion Siaca accept Medicare assignment?
Yes. Medicare's clinician data says Maria D. Encarnacion Siaca accepts Medicare assignment (the Medicare-approved amount as full payment for covered services), as of October 2, 2026. Ask the office to confirm before your visit.
How many Medicare patients does Maria D. Encarnacion Siaca see?
In 2024, CMS data shows 22 Original Medicare patients and 84 services for Maria D. Encarnacion Siaca. This counts Original Medicare only and measures volume, not quality.
What is Maria D. Encarnacion Siaca's NPI number?
1750353017. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.

Medicare activity in 2024

Official CMS public-use data for Maria D. Encarnacion Siaca, data year 2024 (released May 21, 2026). It covers Original Medicare (fee-for-service) patients only, not Medicare Advantage or other insurance. It shows volume, not quality or outcomes. CMS hides any count of 10 or fewer patients.

Original Medicare patients22
Services billed to Medicare84
Different services or procedures3
Participating Medicare providerYes
Average age of these patients79

Most frequent services

  1. Established patient office or other outpatient visit with low level od decision making, if using time, 20 minutes or more (99213)82 services

Chronic conditions among these patients

Share of this clinician’s Original Medicare patients with each condition, as published by CMS (it describes the patients, not the care given).

  • High blood pressure75%
  • High cholesterol75%
  • Diabetes59%

Practice locations

Addresses where Maria D. Encarnacion Siaca is enrolled with Medicare (CMS data updated October 2, 2026).

Specialties

Find other Internal Medicine doctors in Puerto Rico →

Other internal medicine doctors in Fajardo

Clinicians with the same Medicare primary specialty in Fajardo, PR — not a recommendation.

All internal medicine doctors in Fajardo →

Clinician information

CredentialMD
Medical schoolUniversity Central Del Caribe Escuela De Medicina
Graduation year1994 (32 years since medical school)
Gender (as listed)Female
Medicare assignmentAccepts (Medicare-approved amount as full payment)
NPI (National Provider Identifier)1750353017
CorrectionsReport an error or suggest an update →

Most corrections must be made at the source: clinicians update their NPI Registry record (NPPES) and their Medicare enrollment (PECOS); this page follows the next data release.

Sources

  1. National Downloadable File (Doctors and Clinicians) — CMS, data updated October 2, 2026, retrieved October 29, 2026
  2. Medicare Physician & Other Practitioners - by Provider — CMS, data year 2024, released May 21, 2026; Medicare Physician & Other Practitioners - by Provider and Service
  3. NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
  4. Medicare Care Compare — official Medicare tool to look up clinicians