2026 NPPES data Internal Medicine Physician NPI 1689121634 MD
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PAOLA MERCADO MILLAN, MD

Internal Medicine Physician in SANTURCE, Puerto Rico. CMS National Plan and Provider Enumeration System profile including specialty classification, practice address, and Medicare prescribing data when reported.

Federal data — no proprietary rating. PlainDoctor publishes the actual CMS NPPES and Medicare records — NPI registration, specialty, practice location, and prescribing data — without a composite score or editorial opinion on top. Every field traces to a federal source.
Prescribing volume
510
Medicare Part D claims · 80 beneficiaries · Internal Medicine Physician avg: 3K
Generic prescribing
82%
generic claims · 18% brand-name · higher generic rates reduce patient out-of-pocket costs
Industry payments
$516.8
17 payments · CMS Open Payments (Sunshine Act)

What the federal data shows

PAOLA MERCADO MILLAN, MD filed 510 Medicare Part D claims in 2023 as a Internal Medicine Physician in SANTURCE, Puerto Rico, prescribing 82% generic.

510
Part D claims, 2023
82%
generic prescribing
Likely
board-certified (heuristic)

Every figure on this page comes straight from federal CMS records (NPPES, Medicare Part D, MIPS, Open Payments) — no proprietary rating or editorial opinion is applied.

PAOLA MERCADO MILLAN, MD's Medicare Part D volume vs every U.S. prescriber

Total Medicare Part D claims, 2023 — across all CMS prescribers nationally

510 Top 34% higher than 66% of 1,370,886 prescribers

0–200: 670,926 prescribers (49%). Below this entry. 200–400: 182,923 prescribers (13%). Below this entry. 400–600: 90,619 prescribers (7%). This entry sits in this band. 600–800: 56,224 prescribers (4%). Above this entry. 800–1,000: 40,919 prescribers (3%). Above this entry. 1,000–1,200: 31,827 prescribers (2%). Above this entry. 1,200–1,400: 26,224 prescribers (2%). Above this entry. 1,400–1,600: 21,710 prescribers (2%). Above this entry. 1,600–1,800: 19,072 prescribers (1%). Above this entry. 1,800–2,000: 16,451 prescribers (1%). Above this entry. 2,000–2,200: 213,991 prescribers (16%). Above this entry. This provider 0 2K+ every Part D prescriber (claims/yr), bucketed by value

Each bar is a band; taller bars hold more prescribers. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count, share, and where it sits relative to this entry.

Source CMS Medicare Part D Prescriber Public Use File · 2023

Board certification likely (heuristic — not verified)

PAOLA MERCADO MILLAN, MD practices in an ABMS-board-eligible specialty and shows active CMS Medicare participation + 1 hospital affiliation — signals consistent with board-certified status. For verified board certification, see CertificationMatters.org (the official ABMS public lookup).

What does the federal data show about PAOLA MERCADO MILLAN, MD?

Quality data not reported

NPI registry status

Active

Issued 09/07/2016

NPI 1689121634

Primary specialty

Internal Medicine Physician

High-volume

172,858 US NPIs in this specialty

Medicare Part D claims

510 81% vs specialty avg

2023 prescription claims

Specialty avg: 2,716

Specialty distribution in Puerto Rico

How Internal Medicine Physician compares to other specialties among Puerto Rico providers

Puerto Rico providers

Internal Medicine Physician share within Puerto Rico

1. Internal Medicine Physician42%2. Internal medicine21%3. Family medicine17%4. Surgical12%5. Pediatric8%
Internal Medicine Physician share within Puerto Rico

Specialty board-certification context

Estimated specialty board-certified rate — Internal Medicine Physician (ABMS / AOA reference)

Quality data not reported
Est. board-certified rate
78%
Internal Medicine Physician ABMS/AOA estimate

Est. board-certified rate (Internal Medicine Physician) — ABMS / AOA estimate

0%100%78%
Est. board-certified rate (Internal Medicine Physician) — ABMS / AOA estimate

The Merit-based Incentive Payment System (MIPS) scores providers 0–100 across four performance categories: Quality, Cost, Promoting Interoperability, and Improvement Activities, weighted under 42 CFR §414.1380. Reporting is voluntary for many small practices, so absence of a MIPS score is not a quality signal.

Board certification through an ABMS or AOA member board signals voluntary post-licensure examination plus continuous Maintenance of Certification cycles. Verify any individual provider's status through certificationmatters.org (ABMS) or osteopathic.org (AOA).

PAOLA MERCADO MILLAN, MD appears in the CMS NPPES registry as a Internal Medicine Physician provider holding MD credentials at 1395 CALLE SAN RAFAEL # 20, SANTURCE, PR, 00909, with a listed phone of (787) 999-7620. NPI 1689121634 was issued on 09/07/2016. Because NPPES data is self-reported by the provider and refreshed monthly, the address, phone, and specialty reflect what MERCADO MILLAN most recently submitted to CMS rather than a vetted directory listing, which is why patients should always confirm the practice is still at this location before scheduling.

Medicare Part D records for calendar year 2023 show 510 prescription claims written by this provider, covering 80 Medicare beneficiaries and totaling roughly $56K in drug spend, split 18% brand-name and 82% generic by claim count. These figures capture only Medicare Part D — commercial insurance, Medicaid, and cash-pay prescriptions are not included, and any drug-beneficiary cell under 11 is suppressed by CMS for patient privacy.

Internal Medicine Physician is a high-volume specialty nationwide, with 172,858 enrolled providers across 56 states and an average of 2,716 Part D claims per prescriber, so the context for interpreting these metrics differs meaningfully from a primary-care baseline. Important: PlainDoctor is a directory of publicly available government data, not medical advice, a malpractice database, or a quality rating. Inclusion here does not imply a recommendation, and absence of complaints or sanctions on this page does not mean none exist — always verify credentials through the NPPES NPI Registry, your state medical board, and the ABMS or AOA before making healthcare decisions.

Practice Address

1395 CALLE SAN RAFAEL # 20
SANTURCE, PR 00909

Provider Details

NPI 1689121634
Specialty Internal Medicine Physician
Credentials MD
Gender Female
NPI Issued 09/07/2016

Hospital and facility affiliations

Facilities where PAOLA MERCADO MILLAN, MD bills Medicare from. Star ratings (1-5) are CMS Hospital Compare's "Hospital overall rating" — a composite of mortality, readmission, patient experience, safety, timely care, and efficient use of medical imaging measures. Source: CMS Care Compare.

CCS PSC
MANATI, PR

Affiliations sourced from CMS Doctors and Clinicians National Downloadable File; hospital ratings from CMS Hospital General Information dataset (cross-referenced by facility name + state).

Industry payments received (2024) — CMS Open Payments transparency data

The federal Physician Payments Sunshine Act (part of the Affordable Care Act) requires drug and medical-device manufacturers + group purchasing organizations to publicly report payments and other transfers of value to physicians and teaching hospitals. The data below covers 2024 for PAOLA MERCADO MILLAN, MD. Source: openpaymentsdata.cms.gov.

Total received

$517

Largest payer

Medtronic, Inc.

Most common payment type

Food and Beverage

Industry payments are not necessarily indicators of bias — they include research funding, consulting fees for evidence-based work, royalties for inventions, food at conferences, and similar items. The disclosure exists for transparency. Read our methodology for how we interpret this data.

Brand vs generic prescribing mix · Typical

PAOLA MERCADO MILLAN, MD — brand share 18.0%
Specialty average (est.)

18% brand-name claims vs 82% generic, on 510 2023 Medicare Part D claims.

The federal Medicare Part D Generic Dispensing Rate national benchmark sits near 90% generic / 10% brand for primary-care prescribers, per CMS Office of the Actuary 2024 estimates. Higher brand share is common in specialty prescribing where generic equivalents are not available.

Medicare Part D Prescribing Data

CMS Medicare Part D prescriber-level data for calendar year 2023.

510
Total Claims
$56K
Total Drug Cost
80
Medicare Beneficiaries

Prescribing Breakdown

30-Day Fills
569
Total Day Supply
16,732
Brand vs Generic
18% brand / 82% generic
Brand Drug Cost
$50K
Generic Drug Cost
$5K

Patient Demographics

Average Patient Age
74.5 years
Avg HCC Risk Score
2.49
Gender Split
56% female / 44% male

Top Prescribed Drugs (Medicare Part D)

Top drugs by claim count for calendar year 2023. Based on Medicare Part D data only.

What PAOLA MERCADO MILLAN, MD prescribes most

Top Medicare Part D drugs by claim count, 2023

claims
Source CMS Medicare Part D Prescriber Public Use File As of 2023
Drug Claims
Atorvastatin Calcium
41
Metoprolol Succinate
35
Jardiance
Empagliflozin
32
Pantoprazole Sodium
27
Lisinopril
26
Amlodipine Besylate
25
Losartan Potassium
25
Carvedilol
22
Eliquis
Apixaban
20
Furosemide
19

* Counts below 11 are suppressed by CMS for patient privacy. Generic names shown where available from CMS Part D data.

Internal Medicine Physician Overview

How PAOLA MERCADO MILLAN, MD fits within the Internal Medicine Physician landscape nationally.

172,858
Internal Medicine Physician Providers in US
56
States with Internal Medicine Physician
2,716
Avg Claims per Provider

PAOLA MERCADO MILLAN, MD's 510 claims are below the specialty average of 2,716.

Nearby Internal Medicine Physician Providers in Puerto Rico

Other clinicians with the same primary specialty enrolled in Puerto Rico, drawn from the same CMS NPPES roster as MERCADO MILLAN.

Compare Internal Medicine Physician nationally: see state-by-state distribution →

Frequently Asked Questions

What is PAOLA MERCADO MILLAN, MD's specialty?
PAOLA MERCADO MILLAN, MD specializes in Internal Medicine Physician and practices in SANTURCE, Puerto Rico. Credentials: MD.
How much does PAOLA MERCADO MILLAN, MD prescribe under Medicare Part D?
In 2023, PAOLA MERCADO MILLAN, MD wrote 510 Medicare Part D claims totaling $56K in drug costs for 80 beneficiaries.
Where is PAOLA MERCADO MILLAN, MD located?
PAOLA MERCADO MILLAN, MD is located at 1395 CALLE SAN RAFAEL # 20, SANTURCE, PR, 00909. Phone: (787) 999-7620.
What is PAOLA MERCADO MILLAN, MD's NPI number?
PAOLA MERCADO MILLAN, MD's National Provider Identifier (NPI) is 1689121634, issued on 09/07/2016.
Does PAOLA MERCADO MILLAN, MD prescribe more brand-name or generic drugs?
PAOLA MERCADO MILLAN, MD's prescribing is 18% brand-name and 82% generic drugs by claim count, with $50K in brand drug costs.
How many Internal Medicine Physician providers are there in the US?
There are 172,858 Internal Medicine Physician providers across 56 states in the US. The average Internal Medicine Physician provider writes 2,716 Medicare Part D claims per year.
What drugs does PAOLA MERCADO MILLAN, MD prescribe most often?
Based on 2023 Medicare Part D data, PAOLA MERCADO MILLAN, MD's most frequently prescribed drugs include Atorvastatin Calcium, Metoprolol Succinate, Jardiance. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does PAOLA MERCADO MILLAN, MD accept Medicare?
PAOLA MERCADO MILLAN, MD appears in CMS Medicare data with 510 Part D claims and 80 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify PAOLA MERCADO MILLAN, MD's credentials?
PAOLA MERCADO MILLAN, MD's NPI is 1689121634 with credentials MD. You can verify this through the NPPES NPI Registry, check state medical board records, and confirm board certification through the ABMS or AOA.

Data Sources

Provider Directory
CMS National Plan and Provider Enumeration System (NPPES), download.cms.gov/nppes, updated monthly. Contains NPI, specialty, credentials, and practice location.
Specialty Classification
NUCC Health Care Provider Taxonomy (nucc.org), the industry standard for classifying provider specialties in Medicare and Medicaid billing.
Prescribing Data
CMS Medicare Part D Prescriber Public Use File (2023). Includes claims, drug costs, beneficiaries, and opioid prescribing rates.
Limitations
Provider data is self-reported to CMS. Prescribing data reflects Medicare Part D only and does not include commercial insurance, Medicaid, or cash prescriptions. Claims below 11 beneficiaries are suppressed by CMS for privacy.

See our complete data methodology for details on how we collect and process government data.

Data as of April 2026 (NPPES) / 2023 (Medicare Part D). Source: Centers for Medicare & Medicaid Services (CMS).

Disclaimer: Data from CMS NPPES and Medicare Part D. PlainDoctor does not rate or rank providers. Provider information is self-reported and may not be current. Always verify information directly with the provider. About · Methodology