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2026 NPPES data Internal Medicine Physician NPI 1386882520 M.D.
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Nicolas Melgarejo, M.D.

Internal Medicine Physician in San Antonio, Texas.

This profile is drawn from the federal National Provider Identifier Registry (CMS NPPES), which lists more than 7 million U.S. healthcare providers - including 172,737 in Internal Medicine Physician, and covers specialty classification, practice address, and Medicare Part D prescribing data when reported. According to CMS, every field reflects the provider's official federal registration, see our methodology.

Federal data, no proprietary rating. We show these CMS records as-is - no composite score, no star rating, no editorial opinion layered on top.
Prescribing volume
545
Medicare Part D claims · 64 beneficiaries · Internal Medicine Physician avg: 3K
MIPS score
59.1/100
▼ 24 pts below national avg 83.5 · Mid-tier
Industry payments
$676.44
30 payments · CMS Open Payments (Sunshine Act)
Verify NPI on CMS Methodology
Compiled from official public sources by the editorial process.

What the federal data shows

Nicolas Melgarejo, M.D. reported a CMS MIPS final score of 59.1/100 - below the 83.5 national average - and filed 545 Medicare Part D claims in 2023.

59.1/100
MIPS score · -24 vs avg
545
Part D claims, 2023
Likely
board-certified (heuristic)
≥6th
pct among measured MIPS (lower-bound band)

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.

Nicolas Melgarejo, M.D.'s MIPS score vs every measured U.S. clinician

CMS Merit-based Incentive Payment System (MIPS) final score, 2023, the federal quality measure. Clinicians whose score CMS assigned without scoring any category are excluded.

59 ≥ 6th percentile 6% of 454,083 measured providers are in lower value bands

0–10: 8,684 measured providers (2%). Below this entry. 10–20: 3,008 measured providers (1%). Below this entry. 20–30: 3,069 measured providers (1%). Below this entry. 30–40: 2,746 measured providers (1%). Below this entry. 40–50: 2,928 measured providers (1%). Below this entry. 50–60: 5,882 measured providers (1%). This entry sits in this band. 60–70: 13,906 measured providers (3%). Above this entry. 70–80: 94,570 measured providers (21%). Above this entry. 80–90: 129,887 measured providers (29%). Above this entry. 90+: 189,403 measured providers (42%). Above this entry. This provider 0 100 every measured MIPS clinician, bucketed by value

Each bar is a band; taller bars hold more measured providers. 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.

The percentile is a conservative whole-score-point band: it counts only measured clinicians in lower score bands. A CMS MIPS metric is not a recommendation or a clinical-quality rating by PlainDoctor. See methodology § corpus placement.

Source CMS Merit-based Incentive Payment System (MIPS) · 2023

Where Nicolas Melgarejo, M.D. sits

This provider among internal medicine physician peers

Across the 34,612 internal medicine physician providers who report both Medicare Part D prescribing and a MIPS quality score, Nicolas Melgarejo, M.D. writes more Part D claims than 47% of them and scores higher on MIPS quality than 7% - placing this provider in the lower-volume, lower-quality quadrant. Volume reflects patient-panel size and specialty, not quality; the two axes are independent.

Part D claim volume vs MIPS quality, by specialty percentile

Lower volume · High qualityHigh volume · High qualityLower volume · Lower qualityHigh volume · Lower quality02550751000255075100Part D claim volume, percentile in specialtyMIPS quality, percentilePoint, Part D claim volume, percentile in specialty: 97 · MIPS quality, percentile: 87Point, Part D claim volume, percentile in specialty: 43 · MIPS quality, percentile: 65Point, Part D claim volume, percentile in specialty: 83 · MIPS quality, percentile: 45Point, Part D claim volume, percentile in specialty: 30 · MIPS quality, percentile: 40Point, Part D claim volume, percentile in specialty: 78 · MIPS quality, percentile: 42Point, Part D claim volume, percentile in specialty: 3 · MIPS quality, percentile: 83Point, Part D claim volume, percentile in specialty: 42 · MIPS quality, percentile: 35Point, Part D claim volume, percentile in specialty: 95 · MIPS quality, percentile: 50Point, Part D claim volume, percentile in specialty: 67 · MIPS quality, percentile: 93Point, Part D claim volume, percentile in specialty: 20 · MIPS quality, percentile: 97Point, Part D claim volume, percentile in specialty: 37 · MIPS quality, percentile: 58Point, Part D claim volume, percentile in specialty: 27 · MIPS quality, percentile: 20Point, Part D claim volume, percentile in specialty: 28 · MIPS quality, percentile: 15Point, Part D claim volume, percentile in specialty: 92 · MIPS quality, percentile: 0Point, Part D claim volume, percentile in specialty: 72 · MIPS quality, percentile: 90Point, Part D claim volume, percentile in specialty: 15 · MIPS quality, percentile: 13Point, Part D claim volume, percentile in specialty: 0 · MIPS quality, percentile: 22Point, Part D claim volume, percentile in specialty: 47 · MIPS quality, percentile: 25Point, Part D claim volume, percentile in specialty: 68 · MIPS quality, percentile: 75Point, Part D claim volume, percentile in specialty: 57 · MIPS quality, percentile: 97Point, Part D claim volume, percentile in specialty: 75 · MIPS quality, percentile: 3Point, Part D claim volume, percentile in specialty: 7 · MIPS quality, percentile: 48Point, Part D claim volume, percentile in specialty: 23 · MIPS quality, percentile: 53Point, Part D claim volume, percentile in specialty: 48 · MIPS quality, percentile: 12Point, Part D claim volume, percentile in specialty: 52 · MIPS quality, percentile: 18Point, Part D claim volume, percentile in specialty: 22 · MIPS quality, percentile: 28Point, Part D claim volume, percentile in specialty: 80 · MIPS quality, percentile: 75Point, Part D claim volume, percentile in specialty: 98 · MIPS quality, percentile: 2Point, Part D claim volume, percentile in specialty: 87 · MIPS quality, percentile: 47Point, Part D claim volume, percentile in specialty: 85 · MIPS quality, percentile: 72Point, Part D claim volume, percentile in specialty: 35 · MIPS quality, percentile: 82Point, Part D claim volume, percentile in specialty: 73 · MIPS quality, percentile: 27Point, Part D claim volume, percentile in specialty: 12 · MIPS quality, percentile: 17Point, Part D claim volume, percentile in specialty: 90 · MIPS quality, percentile: 38Point, Part D claim volume, percentile in specialty: 25 · MIPS quality, percentile: 30Point, Part D claim volume, percentile in specialty: 5 · MIPS quality, percentile: 60Point, Part D claim volume, percentile in specialty: 58 · MIPS quality, percentile: 68Point, Part D claim volume, percentile in specialty: 82 · MIPS quality, percentile: 5Point, Part D claim volume, percentile in specialty: 77 · MIPS quality, percentile: 57Point, Part D claim volume, percentile in specialty: 88 · MIPS quality, percentile: 23Point, Part D claim volume, percentile in specialty: 38 · MIPS quality, percentile: 87Point, Part D claim volume, percentile in specialty: 8 · MIPS quality, percentile: 73Point, Part D claim volume, percentile in specialty: 33 · MIPS quality, percentile: 85Point, Part D claim volume, percentile in specialty: 65 · MIPS quality, percentile: 8Point, Part D claim volume, percentile in specialty: 18 · MIPS quality, percentile: 70Point, Part D claim volume, percentile in specialty: 70 · MIPS quality, percentile: 67Point, Part D claim volume, percentile in specialty: 40 · MIPS quality, percentile: 43Point, Part D claim volume, percentile in specialty: 50 · MIPS quality, percentile: 7Point, Part D claim volume, percentile in specialty: 2 · MIPS quality, percentile: 62Point, Part D claim volume, percentile in specialty: 63 · MIPS quality, percentile: 95Point, Part D claim volume, percentile in specialty: 45 · MIPS quality, percentile: 32Point, Part D claim volume, percentile in specialty: 10 · MIPS quality, percentile: 55Point, Part D claim volume, percentile in specialty: 13 · MIPS quality, percentile: 80Point, Part D claim volume, percentile in specialty: 32 · MIPS quality, percentile: 62Point, Part D claim volume, percentile in specialty: 60 · MIPS quality, percentile: 97Point, Part D claim volume, percentile in specialty: 17 · MIPS quality, percentile: 78Point, Part D claim volume, percentile in specialty: 93 · MIPS quality, percentile: 92Point, Part D claim volume, percentile in specialty: 55 · MIPS quality, percentile: 52Point, Part D claim volume, percentile in specialty: 100 · MIPS quality, percentile: 33Point, Part D claim volume, percentile in specialty: 62 · MIPS quality, percentile: 35Nicolas Melgarejo, M.D., Part D claim volume, percentile in specialty: 47 · MIPS quality, percentile: 7
Part D claim volume vs MIPS quality, by specialty percentile

Each dot is one internal medicine physician peer from a representative sample of 60; the gold marker is Nicolas Melgarejo, M.D.. Source: CMS Medicare Part D Prescriber data and the CMS Merit-based Incentive Payment System, 2023.

✓
Board certification likely (heuristic, not verified)

Nicolas Melgarejo, M.D. practices in an ABMS-board-eligible specialty and shows active CMS Medicare participation + MIPS quality reporting + 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 Nicolas Melgarejo, M.D.?

Below national average

NPI registry status

Active

Issued 01/26/2009

NPI 1386882520

Primary specialty

Internal Medicine Physician

High-volume

172,737 US NPIs in this specialty

Medicare Part D claims

545 80% vs specialty avg

2023 prescription claims

Specialty avg: 2,716

MIPS final score

59.1/100 24.4 pts vs avg

Mid-tier band

vs 83.5 national avg

Specialty distribution in Texas

How Internal Medicine Physician compares to other specialties among Texas providers

Texas providers
Behavior Technician5.6%Student in an Organized Heal…5.1%Family Nurse Practitioner4.5%Professional Counselor4.4%Pharmacist4.4%Speech-Language Pathologist3.9%Internal Medicine Physician2.6%
Largest specialties in Texas (% of in-state providers)

Medicare quality performance, MIPS

Nicolas Melgarejo, M.D.'s 2023 MIPS final score plotted against the Internal Medicine Physician national average

Below national average
MIPS Final Score
59.1/100
vs 83.5 national avg · 2023 performance year

MIPS final score (Internal Medicine Physician) - 59.1/100 vs national avg 83.5

0%100%National avg84%59.1%
MIPS final score (Internal Medicine Physician) - 59.1/100 vs national avg 83.5
How MIPS and board certification work

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).

Nicolas Melgarejo, M.D. appears in the CMS NPPES registry as an Internal Medicine Physician provider holding M.D. credentials at 343 W. HOUSTON ST., San Antonio, TX, 78205, with a listed phone of (210) 224-9616. NPI 1386882520 was issued on 01/26/2009.

Medicare Part D records for calendar year 2023 show 545 prescription claims written by this provider, covering 64 Medicare beneficiaries and totaling roughly $921K in drug spend. On the CMS Merit-based Incentive Payment System, this provider earned a Final Score of 59.1/100 for the 2023 performance year (Quality 54.5, Cost 67), compared with the 83.5 average among clinicians with a measured score.

Internal Medicine Physician is a high-volume specialty nationwide, with 172,737 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

343 W. HOUSTON ST.
San Antonio, TX 78205
(210) 224-9616

Provider Details

NPI 1386882520
Specialty Internal Medicine Physician
Credentials M.D.
Gender Male
NPI Issued 01/26/2009

CMS Quality Score (MIPS)

Merit-based Incentive Payment System (MIPS) scores from CMS, 2023 performance year.

59.0622
Final Score
Measured-score avg: 83.5
54.5332
Quality
67.021
Cost
0
Promoting Interoperability

Reporting: Group practice

Hospital and facility affiliations

Facilities where Nicolas Melgarejo, 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.

San Antonio Infectious Diseases Consultants
San Antonio, TX

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 Nicolas Melgarejo, M.D.. Source: openpaymentsdata.cms.gov.

Total received

$676

Largest payer

Gilead Sciences, 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.

License & disciplinary context - Texas TMB 2023 annual report

Aggregate state board data only, NOT a determination of any individual provider's status. The figures below describe statewide disciplinary activity across all ~77K Texas medical licensees in 2023 - they are NOT specific to Nicolas Melgarejo, M.D.. To verify Nicolas Melgarejo, M.D.'s current license status, search the TMB public license lookup directly, or check the Federation of State Medical Boards (FSMB) verification service.

344
Total board actions, Texas 2023
Across 334 cases
4.47
Actions per 1,000 licensees
Texas statewide rate
probation
Most common action type
94 cases

TMB publishes annual disciplinary statistics as part of public-record reporting under each state's Administrative Procedure Act. See the full breakdown by action type and year on the Texas disciplinary trends page. Cross-checked against FSMB U.S. Medical Regulatory Trends.

Medicare Part D Prescribing Data

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

545
Total Claims
$921K
Total Drug Cost
64
Medicare Beneficiaries

Prescribing Breakdown

30-Day Fills
679
Total Day Supply
19,573
Generic Drug Cost
$74K
Antibiotic Claims
222

Patient Demographics

Average Patient Age
71.5 years
Avg HCC Risk Score
2.60
Gender Split
47% female / 53% male

Top Prescribed Drugs (Medicare Part D)

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

What Nicolas Melgarejo, 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
Biktarvy
Bictegrav/Emtricit/Tenofov Ala
63
Doxycycline Monohydrate
 55
Amoxicillin
 48
Genvoya
Elviteg/Cob/Emtri/Tenof Alafen
36
Doxycycline Hyclate
 27
Prezcobix
Darunavir/Cobicistat
23
Tivicay
Dolutegravir Sodium
23
Levofloxacin
 20
Ritonavir
 16
Triumeq
Abacavir/Dolutegravir/Lamivudi
16

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

More Internal Medicine Physician in TX → All providers in Texas → Compare specialties →

Internal Medicine Physician Overview

How Nicolas Melgarejo, M.D. fits within the Internal Medicine Physician landscape nationally.

172,737
Internal Medicine Physician Providers in US
56
States with Internal Medicine Physician
2,716
Avg Claims per Provider

Nicolas Melgarejo, M.D.'s 545 claims are below the specialty average of 2,716.

Nearby Internal Medicine Physician Providers in Texas

Other clinicians with the same primary specialty enrolled in Texas, drawn from the same CMS NPPES roster as Melgarejo.

Dr. Muhammad A. Sattar
MD
Dallas, TX
Anunaya Aashish
Denton, TX
Dr. Queenie Ann Abad
M.D.
San Antonio, TX
Dr. Fuad Abaleka
M.D
Lubbock, TX
Dr. Carol Abalihi
M.D.
El Paso, TX

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

Before you book an appointment

Use this federal record as your verification checklist, not as a recommendation.

  • Confirm the NPI record is current in the official CMS registry, providers update their own NPPES details, and moves can lag. Verify this NPI
  • Check the active license and any disciplinary history with the Texas medical board, federal registration is not a license check. Credential verification guide
  • Weigh a second option: compare this provider with a nearby Internal Medicine Physician peer on Medicare volume and prescribing patterns. Compare providers

Medicare Part D and MIPS figures describe practice patterns in federal programs only, they are not quality ratings, and PlainDoctor does not rate, rank, or recommend providers.

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Frequently Asked Questions

What is Nicolas Melgarejo, M.D.'s specialty? ▼
Nicolas Melgarejo, M.D. specializes in Internal Medicine Physician and practices in San Antonio, Texas. Credentials: M.D..
How much does Nicolas Melgarejo, M.D. prescribe under Medicare Part D? ▼
In 2023, Nicolas Melgarejo, M.D. wrote 545 Medicare Part D claims totaling $921K in drug costs for 64 beneficiaries.
What is Nicolas Melgarejo, M.D.'s Medicare quality score? ▼
Nicolas Melgarejo, M.D. has a CMS MIPS Final Score of 59.1/100 (Quality: 54.5, Cost: 67). The average MIPS Final Score across the 454,083 clinicians with at least one published category score is 83.5; clinicians whose score CMS assigned without scoring any category are excluded from that average. Source: CMS Merit-based Incentive Payment System (MIPS) 2023.
Where is Nicolas Melgarejo, M.D. located? ▼
Nicolas Melgarejo, M.D. is located at 343 W. HOUSTON ST., San Antonio, TX, 78205. Phone: (210) 224-9616.
What is Nicolas Melgarejo, M.D.'s NPI number? ▼
Nicolas Melgarejo, M.D.'s National Provider Identifier (NPI) is 1386882520, issued on 01/26/2009.
How many Internal Medicine Physician providers are there in the US? ▼
There are 172,737 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 Nicolas Melgarejo, M.D. prescribe most often? ▼
Based on 2023 Medicare Part D data, Nicolas Melgarejo, M.D.'s most frequently prescribed drugs include Biktarvy, Doxycycline Monohydrate, Amoxicillin. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does Nicolas Melgarejo, M.D. accept Medicare? ▼
Nicolas Melgarejo, M.D. appears in CMS Medicare data with 545 Part D claims and 64 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify Nicolas Melgarejo, M.D.'s credentials? ▼
Nicolas Melgarejo, M.D.'s NPI is 1386882520 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

View source datasets and methodology notes
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.
Quality Performance
CMS Merit-based Incentive Payment System (MIPS) - 2023 performance year.
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

Compiled from official public sources by the editorial process.

Every figure on PlainDoctor is rendered directly from the federal CMS NPPES registry, Medicare Part D, MIPS, and Open Payments records, no number is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of May 2026.