NPI registry status
Active
2026 NPPES data Internal Medicine Physician NPI 1588648422 MD
Verify on CMS → Afonso Ferreira, MD
Internal Medicine Physician in Caro, Michigan.
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
5K
Medicare Part D claims · 418 beneficiaries · Internal Medicine Physician avg: 3K
Generic prescribing
87%
generic claims · 11% brand-name · higher generic rates reduce patient out-of-pocket costs
Source: CMS Medicare Part D Prescriber Public Use File, 2023
What the federal data shows
Afonso Ferreira, MD filed 4,795 Medicare Part D claims in 2023 as an Internal Medicine Physician in Caro, Michigan, prescribing 87% generic.
- 5K
- Part D claims, 2023
- 87%
- 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.
Afonso Ferreira, MD's Medicare Part D volume vs every U.S. prescriber
Total Medicare Part D claims, 2023, across all CMS prescribers nationally
4,795 Top 7% higher than 93% 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)
Afonso Ferreira, 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 Afonso Ferreira, MD?
Quality data not reportedPrimary specialty
Internal Medicine Physician
Medicare Part D claims
4,795 77% vs specialty avg
Specialty distribution in Michigan
How Internal Medicine Physician compares to other specialties among Michigan 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 Internal Medicine 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).
Afonso Ferreira, MD appears in the CMS NPPES registry as an Internal Medicine Physician provider holding MD credentials at 465 N. HOOPER ST, Caro, MI, 48723, with a listed phone of (989) 672-1555. NPI 1588648422 was issued on 12/05/2005.
Medicare Part D records for calendar year 2023 show 4,795 prescription claims written by this provider, covering 418 Medicare beneficiaries and totaling roughly $630K in drug spend, split 11% brand-name and 87% generic by claim count, with an opioid prescribing rate of 1.5%.
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
Provider Details
| NPI | 1588648422 |
|---|---|
| Specialty | Internal Medicine Physician |
| Credentials | MD |
| Gender | Male |
| NPI Issued | 12/05/2005 |
License & disciplinary context - Michigan MI-BOM 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 ~41K Michigan medical licensees in 2023 - they are NOT specific to Afonso Ferreira, MD. To verify Afonso Ferreira, MD's current license status, search the MI-BOM public license lookup directly, or check the Federation of State Medical Boards (FSMB) verification service.
123
Total board actions, Michigan 2023
Across 120 cases
3.00
Actions per 1,000 licensees
Michigan statewide rate
probation
Most common action type
44 cases
MI-BOM 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 Michigan disciplinary trends page. Cross-checked against FSMB U.S. Medical Regulatory Trends.
Brand vs generic prescribing mix · Typical
Afonso Ferreira, MD - brand share 11.0%
Internal Medicine Physician average
11% brand-name claims vs 87% generic, on 4,795 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.
4,795
Total Claims
$630K
Total Drug Cost
418
Medicare Beneficiaries
Prescribing Breakdown
- 30-Day Fills
- 11,520
- Total Day Supply
- 340,873
- Brand vs Generic
- 11% brand / 87% generic
- Brand Drug Cost
- $497K
- Generic Drug Cost
- $129K
- Opioid Claims
- 70 (1.5% rate)
- Antibiotic Claims
- 65
Patient Demographics
- Average Patient Age
- 76.4 years
- Avg HCC Risk Score
- 1.34
- Gender Split
- 51% female / 49% male
- Age Distribution
- <65: 24, 65-74: 157, 75-84: 153, 85+: 84
Top Prescribed Drugs (Medicare Part D)
Top drugs by claim count for calendar year 2023. Based on Medicare Part D data only.
What Afonso Ferreira, MD prescribes most
Top Medicare Part D drugs by claim count, 2023
- Amlodipine Besylate
Amlodipine Besylate
228 claims
- Atorvastatin Calcium
Atorvastatin Calcium
204 claims
- Levothyroxine Sodium
Levothyroxine Sodium
186 claims
- Simvastatin
Simvastatin
158 claims
- Metformin Hcl
Metformin Hcl
152 claims
- Losartan Potassium
Losartan Potassium
148 claims
- Omeprazole
Omeprazole
127 claims
- Lisinopril
Lisinopril
126 claims
| Drug | Claims |
|---|---|
| Amlodipine Besylate | 228 |
| Atorvastatin Calcium | 204 |
| Levothyroxine Sodium | 186 |
| Simvastatin | 158 |
| Metformin Hcl | 152 |
| Losartan Potassium | 148 |
| Omeprazole | 127 |
| Lisinopril | 126 |
| Rosuvastatin Calcium | 116 |
| Metoprolol Succinate | 106 |
* 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 Afonso Ferreira, MD 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
Afonso Ferreira, MD's 4,795 claims are above the specialty average of 2,716.
Nearby Internal Medicine Physician Providers in Michigan
Other clinicians with the same primary specialty enrolled in Michigan, drawn from the same CMS NPPES roster as Ferreira.
Dr. Keith Aaronson
MD
Ann Arbor, MI
Dr. Tomas Abalo
M.D.
Iron Mountain, MI
Dr. Ali Abbas
M.D.
Pontiac, MI
Dr. Hawazin Abbas
MD
Auburn Hills, MI
Dr. Imran Abbasi
D.O.
Warren, MI
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 Michigan 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 Afonso Ferreira, MD's specialty? ▼
Afonso Ferreira, MD specializes in Internal Medicine Physician and practices in Caro, Michigan. Credentials: MD.
How much does Afonso Ferreira, MD prescribe under Medicare Part D? ▼
In 2023, Afonso Ferreira, MD wrote 4,795 Medicare Part D claims totaling $630K in drug costs for 418 beneficiaries.
Where is Afonso Ferreira, MD located? ▼
Afonso Ferreira, MD is located at 465 N. HOOPER ST, Caro, MI, 48723. Phone: (989) 672-1555.
What is Afonso Ferreira, MD's NPI number? ▼
Afonso Ferreira, MD's National Provider Identifier (NPI) is 1588648422, issued on 12/05/2005.
Does Afonso Ferreira, MD prescribe more brand-name or generic drugs? ▼
Afonso Ferreira, MD's prescribing is 11% brand-name and 87% generic drugs by claim count, with $497K in brand drug costs.
Does Afonso Ferreira, MD prescribe opioids? ▼
Yes, Afonso Ferreira, MD had 70 opioid claims in 2023 with an opioid prescribing rate of 1.5%.
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 Afonso Ferreira, MD prescribe most often? ▼
Based on 2023 Medicare Part D data, Afonso Ferreira, MD's most frequently prescribed drugs include Amlodipine Besylate, Atorvastatin Calcium, Levothyroxine Sodium. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does Afonso Ferreira, MD accept Medicare? ▼
Afonso Ferreira, MD appears in CMS Medicare data with 4,795 Part D claims and 418 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify Afonso Ferreira, MD's credentials? ▼
Afonso Ferreira, MD's NPI is 1588648422 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
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.