2026 NPPES data Ophthalmology Physician NPI 1649566977 M.D.
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CARLOS FERNANDEZ SANTOS, M.D.

Ophthalmology Physician in CAGUAS, 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
6K
Medicare Part D claims · 1K beneficiaries · Ophthalmology Physician avg: 1K
Generic prescribing
58%
generic claims · 42% brand-name · higher generic rates reduce patient out-of-pocket costs
Industry payments
$527.74
9 payments · CMS Open Payments (Sunshine Act)

What the federal data shows

CARLOS FERNANDEZ SANTOS, M.D. filed 6,242 Medicare Part D claims in 2023 as a Ophthalmology Physician in CAGUAS, Puerto Rico, prescribing 58% generic.

6K
Part D claims, 2023
58%
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.

CARLOS FERNANDEZ SANTOS, M.D.'s Medicare Part D volume vs every U.S. prescriber

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

6,242 Top 5% higher than 95% 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%). Below this entry. 600–800: 56,224 prescribers (4%). Below this entry. 800–1,000: 40,919 prescribers (3%). Below this entry. 1,000–1,200: 31,827 prescribers (2%). Below this entry. 1,200–1,400: 26,224 prescribers (2%). Below this entry. 1,400–1,600: 21,710 prescribers (2%). Below this entry. 1,600–1,800: 19,072 prescribers (1%). Below this entry. 1,800–2,000: 16,451 prescribers (1%). Below this entry. 2,000–2,200: 213,991 prescribers (16%). This entry sits in this band. 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)

CARLOS FERNANDEZ SANTOS, M.D. 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 CARLOS FERNANDEZ SANTOS, M.D.?

Quality data not reported

NPI registry status

Active

Issued 06/24/2011

NPI 1649566977

Primary specialty

Ophthalmology Physician

Mid-sized

22,090 US NPIs in this specialty

Medicare Part D claims

6,242 340% vs specialty avg

2023 prescription claims

Specialty avg: 1,420

Specialty distribution in Puerto Rico

How Ophthalmology Physician compares to other specialties among Puerto Rico providers

Puerto Rico providers

Ophthalmology Physician share within Puerto Rico

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

Specialty board-certification context

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

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

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

0%100%78%
Est. board-certified rate (Ophthalmology 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).

CARLOS FERNANDEZ SANTOS, M.D. appears in the CMS NPPES registry as a Ophthalmology Physician provider holding M.D. credentials at PLAZA BAIROA, CAGUAS, PR, 00725, with a listed phone of (787) 641-3030. NPI 1649566977 was issued on 06/24/2011. Because NPPES data is self-reported by the provider and refreshed monthly, the address, phone, and specialty reflect what FERNANDEZ SANTOS 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 6,242 prescription claims written by this provider, covering 1,320 Medicare beneficiaries and totaling roughly $522K in drug spend, split 42% brand-name and 58% 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.

Ophthalmology Physician is a mid-sized specialty nationwide, with 22,090 enrolled providers across 56 states and an average of 1,420 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

PLAZA BAIROA
CAGUAS, PR 00725

Provider Details

NPI 1649566977
Specialty Ophthalmology Physician
Credentials M.D.
Gender Male
NPI Issued 06/24/2011

Hospital and facility affiliations

Facilities where CARLOS FERNANDEZ SANTOS, M.D. 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.

PUERTO RICO EYE INSTITUTE
CAGUAS, 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 CARLOS FERNANDEZ SANTOS, M.D.. Source: openpaymentsdata.cms.gov.

Total received

$528

Largest payer

Alcon Puerto Rico 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 · Above average

CARLOS FERNANDEZ SANTOS, M.D. — brand share 42.0%
Specialty average (est.)

42% brand-name claims vs 58% generic, on 6,242 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.

6,242
Total Claims
$522K
Total Drug Cost
1,320
Medicare Beneficiaries

Prescribing Breakdown

30-Day Fills
7,355
Total Day Supply
188,251
Brand vs Generic
42% brand / 58% generic
Brand Drug Cost
$445K
Generic Drug Cost
$77K
Antibiotic Claims
14

Patient Demographics

Average Patient Age
72.8 years
Avg HCC Risk Score
1.79
Gender Split
56% female / 44% male
Age Distribution
<65: 164, 65-74: 608, 75-84: 440, 85+: 108

Top Prescribed Drugs (Medicare Part D)

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

What CARLOS FERNANDEZ SANTOS, M.D. 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
Prednisolone Acetate
1,077
Ofloxacin
978
Ketorolac Tromethamine
912
Latanoprost
893
Lumigan
Bimatoprost
808
Dorzolamide-Timolol
Dorzolamide Hcl/Timolol Maleat
456
Brimonidine Tartrate
178
Neomycin-Polymyxin-Dexameth
Neomycin/Polymyxin B/Dexametha
156
Dorzolamide Hcl
127
Timolol Maleate
112

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

Ophthalmology Physician Overview

How CARLOS FERNANDEZ SANTOS, M.D. fits within the Ophthalmology Physician landscape nationally.

22,090
Ophthalmology Physician Providers in US
56
States with Ophthalmology Physician
1,420
Avg Claims per Provider

CARLOS FERNANDEZ SANTOS, M.D.'s 6,242 claims are above the specialty average of 1,420.

Nearby Ophthalmology Physician Providers in Puerto Rico

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

Compare Ophthalmology Physician nationally: see state-by-state distribution →

Frequently Asked Questions

What is CARLOS FERNANDEZ SANTOS, M.D.'s specialty?
CARLOS FERNANDEZ SANTOS, M.D. specializes in Ophthalmology Physician and practices in CAGUAS, Puerto Rico. Credentials: M.D..
How much does CARLOS FERNANDEZ SANTOS, M.D. prescribe under Medicare Part D?
In 2023, CARLOS FERNANDEZ SANTOS, M.D. wrote 6,242 Medicare Part D claims totaling $522K in drug costs for 1,320 beneficiaries.
Where is CARLOS FERNANDEZ SANTOS, M.D. located?
CARLOS FERNANDEZ SANTOS, M.D. is located at PLAZA BAIROA, CAGUAS, PR, 00725. Phone: (787) 641-3030.
What is CARLOS FERNANDEZ SANTOS, M.D.'s NPI number?
CARLOS FERNANDEZ SANTOS, M.D.'s National Provider Identifier (NPI) is 1649566977, issued on 06/24/2011.
Does CARLOS FERNANDEZ SANTOS, M.D. prescribe more brand-name or generic drugs?
CARLOS FERNANDEZ SANTOS, M.D.'s prescribing is 42% brand-name and 58% generic drugs by claim count, with $445K in brand drug costs.
How many Ophthalmology Physician providers are there in the US?
There are 22,090 Ophthalmology Physician providers across 56 states in the US. The average Ophthalmology Physician provider writes 1,420 Medicare Part D claims per year.
What drugs does CARLOS FERNANDEZ SANTOS, M.D. prescribe most often?
Based on 2023 Medicare Part D data, CARLOS FERNANDEZ SANTOS, M.D.'s most frequently prescribed drugs include Prednisolone Acetate, Ofloxacin, Ketorolac Tromethamine. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does CARLOS FERNANDEZ SANTOS, M.D. accept Medicare?
CARLOS FERNANDEZ SANTOS, M.D. appears in CMS Medicare data with 6,242 Part D claims and 1,320 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify CARLOS FERNANDEZ SANTOS, M.D.'s credentials?
CARLOS FERNANDEZ SANTOS, M.D.'s NPI is 1649566977 with credentials M.D.. 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