NPI registry status
Active
2026 NPPES data Gastroenterology Physician NPI 1497894505 MD
Verify on CMS → Mamie Annexy Lopez, MD
Gastroenterology Physician in Manati, Puerto Rico.
This profile is drawn from the federal National Provider Identifier Registry (CMS NPPES), which lists more than 7 million U.S. healthcare providers - including 16,567 in Gastroenterology 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
2K
Medicare Part D claims · 366 beneficiaries · Gastroenterology Physician avg: 833
Generic prescribing
82%
generic claims · 18% brand-name · higher generic rates reduce patient out-of-pocket costs
Source: CMS Medicare Part D Prescriber Public Use File, 2023
Compiled from official public sources by the PlainDoctor editorial team.
What the federal data shows
Mamie Annexy Lopez, MD filed 1,645 Medicare Part D claims in 2023 as a Gastroenterology Physician in Manati, Puerto Rico, prescribing 82% generic.
- 2K
- Part D claims, 2023
- 82%
- generic prescribing
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.
Mamie Annexy Lopez, MD's Medicare Part D volume vs every U.S. prescriber
Total Medicare Part D claims, 2023, across all CMS prescribers nationally
1,645 Top 18% higher than 82% of 1,370,886 prescribers
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-eligible specialty (heuristic, not verified)
Mamie Annexy Lopez, MD practices in an ABMS-board-eligible specialty but we don't have enough CMS-participation signals to confirm active board-certified status. Consult CertificationMatters.org (the official ABMS public lookup).
What does the federal data show about Mamie Annexy Lopez, MD?
Quality data not reportedPrimary specialty
Gastroenterology Physician
Medicare Part D claims
1,645 97% vs specialty avg
Specialty distribution in Puerto Rico
How Gastroenterology Physician compares to other specialties among Puerto Rico providers
Board certification
Not published by CMS
CMS does not publish a per-provider board-certification field in NPPES. PlainDoctor does not have a reliable per-specialty certification rate to show for Gastroenterology Physician. Verify directly:
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).
Mamie Annexy Lopez, MD appears in the CMS NPPES registry as a Gastroenterology Physician provider holding MD credentials at A4 CALLE MARGINAL, Manati, PR, 00674, with a listed phone of (787) 884-5368. NPI 1497894505 was issued on 02/05/2007.
Medicare Part D records for calendar year 2023 show 1,645 prescription claims written by this provider, covering 366 Medicare beneficiaries and totaling roughly $113K in drug spend, split 18% brand-name and 82% generic by claim count.
Gastroenterology Physician is a mid-sized specialty nationwide, with 16,567 enrolled providers across 54 states and an average of 833 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
Provider Details
| NPI | 1497894505 |
|---|---|
| Specialty | Gastroenterology Physician |
| Credentials | MD |
| Gender | Female |
| NPI Issued | 02/05/2007 |
Brand vs generic prescribing mix · Typical
Mamie Annexy Lopez, MD - brand share 18.0%
Gastroenterology Physician average
18% brand-name claims vs 82% generic, on 1,645 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.
1,645
Total Claims
$113K
Total Drug Cost
366
Medicare Beneficiaries
Prescribing Breakdown
- 30-Day Fills
- 1,736
- Total Day Supply
- 39,111
- Brand vs Generic
- 18% brand / 82% generic
- Brand Drug Cost
- $88K
- Generic Drug Cost
- $25K
- Antibiotic Claims
- 30
Patient Demographics
- Average Patient Age
- 70.6 years
- Avg HCC Risk Score
- 1.94
- Gender Split
- 62% female / 38% male
- Age Distribution
- <65: 71, 65-74: 173, 75-84: 108, 85+: 14
Top Prescribed Drugs (Medicare Part D)
Top drugs by claim count for calendar year 2023. Based on Medicare Part D data only.
What Mamie Annexy Lopez, MD prescribes most
Top Medicare Part D drugs by claim count, 2023
- Pantoprazole Sodium
Pantoprazole Sodium
303 claims
- Famotidine
Famotidine
287 claims
- Esomeprazole Magne…
Esomeprazole Magnesium
142 claims
- Omeprazole 98
Omeprazole
98 claims
- Midazolam Hcl 90
Midazolam Hcl
90 claims
- Meperidine Hcl 82
Meperidine Hcl
82 claims
- Creon 80
Creon
80 claims
- Sucralfate 73
Sucralfate
73 claims
| Drug | Claims |
|---|---|
| Pantoprazole Sodium | 303 |
| Famotidine | 287 |
| Esomeprazole Magnesium | 142 |
| Omeprazole | 98 |
| Midazolam Hcl Midazolam Hcl/Pf | 90 |
| Meperidine Hcl Meperidine Hcl/Pf | 82 |
| Creon Lipase/Protease/Amylase | 80 |
| Sucralfate | 73 |
| Linzess Linaclotide | 59 |
* Counts below 11 are suppressed by CMS for patient privacy. Generic names shown where available from CMS Part D data.
Gastroenterology Physician Overview
How Mamie Annexy Lopez, MD fits within the Gastroenterology Physician landscape nationally.
16,567
Gastroenterology Physician Providers in US
54
States with Gastroenterology Physician
833
Avg Claims per Provider
Mamie Annexy Lopez, MD's 1,645 claims are above the specialty average of 833.
Nearby Gastroenterology Physician Providers in Puerto Rico
Other clinicians with the same primary specialty enrolled in Puerto Rico, drawn from the same CMS NPPES roster as Annexy Lopez.
Dr. Yamilka Abreu Delgado
MD
Humacao, PR
Dr. Melvyn Acosta
M.D.
Hato Rey, PR
Dr. Ivan Antunez Gonzalez
M.D.
Guaynabo, PR
Dr. Nestor Aponte-Reyes
MD
Manati, PR
Dr. Javier Arroyo
MD
Humacao, PR
Compare Gastroenterology 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 Puerto Rico medical board, federal registration is not a license check. Credential verification guide
- Weigh a second option: compare this provider with a nearby Gastroenterology 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.
Healthcare Guides
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Frequently Asked Questions
What is Mamie Annexy Lopez, MD's specialty? ▼
Mamie Annexy Lopez, MD specializes in Gastroenterology Physician and practices in Manati, Puerto Rico. Credentials: MD.
How much does Mamie Annexy Lopez, MD prescribe under Medicare Part D? ▼
In 2023, Mamie Annexy Lopez, MD wrote 1,645 Medicare Part D claims totaling $113K in drug costs for 366 beneficiaries.
Where is Mamie Annexy Lopez, MD located? ▼
Mamie Annexy Lopez, MD is located at A4 CALLE MARGINAL, Manati, PR, 00674. Phone: (787) 884-5368.
What is Mamie Annexy Lopez, MD's NPI number? ▼
Mamie Annexy Lopez, MD's National Provider Identifier (NPI) is 1497894505, issued on 02/05/2007.
Does Mamie Annexy Lopez, MD prescribe more brand-name or generic drugs? ▼
Mamie Annexy Lopez, MD's prescribing is 18% brand-name and 82% generic drugs by claim count, with $88K in brand drug costs.
How many Gastroenterology Physician providers are there in the US? ▼
There are 16,567 Gastroenterology Physician providers across 54 states in the US. The average Gastroenterology Physician provider writes 833 Medicare Part D claims per year.
What drugs does Mamie Annexy Lopez, MD prescribe most often? ▼
Based on 2023 Medicare Part D data, Mamie Annexy Lopez, MD's most frequently prescribed drugs include Pantoprazole Sodium, Famotidine, Esomeprazole Magnesium. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does Mamie Annexy Lopez, MD accept Medicare? ▼
Mamie Annexy Lopez, MD appears in CMS Medicare data with 1,645 Part D claims and 366 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify Mamie Annexy Lopez, MD's credentials? ▼
Mamie Annexy Lopez, MD's NPI is 1497894505 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
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.
- 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 PlainDoctor editorial team.