NPI registry status
Active
2026 NPPES data Internal Medicine Physician NPI 1679680805 M.D.
Verify on CMS → John Alferes, M.D.
Internal Medicine Physician in Portland, Oregon.
This profile is drawn from the federal National Provider Identifier Registry (CMS NPPES), which lists more than 7 million U.S. healthcare providers - including 172,858 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
7K
Medicare Part D claims · 845 beneficiaries · Internal Medicine Physician avg: 3K
Generic prescribing
88%
generic claims · 10% 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
John Alferes, M.D. filed 7,005 Medicare Part D claims in 2023 as a Internal Medicine Physician in Portland, Oregon, prescribing 88% generic.
- 7K
- Part D claims, 2023
- 88%
- 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.
John Alferes, M.D.'s Medicare Part D volume vs every U.S. prescriber
Total Medicare Part D claims, 2023, across all CMS prescribers nationally
7,005 Top 4% higher than 96% 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)
John Alferes, M.D. 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 John Alferes, M.D.?
Quality data not reportedPrimary specialty
Internal Medicine Physician
Medicare Part D claims
7,005 158% vs specialty avg
Specialty distribution in Oregon
How Internal Medicine Physician compares to other specialties among Oregon 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).
John Alferes, M.D. appears in the CMS NPPES registry as a Internal Medicine Physician provider holding M.D. credentials at 3550 N INTERSTATE AVE, Portland, OR, 97227, with a listed phone of (503) 285-9321. NPI 1679680805 was issued on 08/24/2006.
Medicare Part D records for calendar year 2023 show 7,005 prescription claims written by this provider, covering 845 Medicare beneficiaries and totaling roughly $303K in drug spend, split 10% brand-name and 88% generic by claim count, with an opioid prescribing rate of 9.0%.
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
Provider Details
| NPI | 1679680805 |
|---|---|
| Specialty | Internal Medicine Physician |
| Credentials | M.D. |
| Gender | Male |
| NPI Issued | 08/24/2006 |
Brand vs generic prescribing mix · Typical
John Alferes, M.D. - brand share 10.0%
Internal Medicine Physician average
10% brand-name claims vs 88% generic, on 7,005 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.
7,005
Total Claims
$303K
Total Drug Cost
845
Medicare Beneficiaries
Prescribing Breakdown
- 30-Day Fills
- 15,841
- Total Day Supply
- 463,259
- Brand vs Generic
- 10% brand / 88% generic
- Brand Drug Cost
- $190K
- Generic Drug Cost
- $110K
- Opioid Claims
- 627 (9.0% rate)
- Antibiotic Claims
- 73
Patient Demographics
- Average Patient Age
- 73.3 years
- Avg HCC Risk Score
- 1.10
- Gender Split
- 44% female / 56% male
- Age Distribution
- <65: 62, 65-74: 429, 75-84: 276, 85+: 78
Top Prescribed Drugs (Medicare Part D)
Top drugs by claim count for calendar year 2023. Based on Medicare Part D data only.
What John Alferes, M.D. prescribes most
Top Medicare Part D drugs by claim count, 2023
- Atorvastatin Calcium
Atorvastatin Calcium
555 claims
- Lisinopril
Lisinopril
325 claims
- Amlodipine Besylate
Amlodipine Besylate
298 claims
- Losartan Potassium
Losartan Potassium
270 claims
- Hydrocodone-Acetam…
Hydrocodone-Acetaminophen
245 claims
- Simvastatin
Simvastatin
241 claims
- Levothyroxine Sodium 185
Levothyroxine Sodium
185 claims
- Oxycodone Hcl 173
Oxycodone Hcl
173 claims
| Drug | Claims |
|---|---|
| Atorvastatin Calcium | 555 |
| Lisinopril | 325 |
| Amlodipine Besylate | 298 |
| Losartan Potassium | 270 |
| Hydrocodone-Acetaminophen Hydrocodone/Acetaminophen | 245 |
| Simvastatin | 241 |
| Levothyroxine Sodium | 185 |
| Oxycodone Hcl | 173 |
| Metoprolol Tartrate | 165 |
| Metformin Hcl | 152 |
* 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 John Alferes, M.D. 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
John Alferes, M.D.'s 7,005 claims are above the specialty average of 2,716.
Nearby Internal Medicine Physician Providers in Oregon
Other clinicians with the same primary specialty enrolled in Oregon, drawn from the same CMS NPPES roster as Alferes.
Dr. Charmaine Clarisse Abalos
M.D.
Medford, OR
Dr. Soraya Abbassian
M.D.
Portland, OR
Dr. Nicholas Abbott
M.D.
Tualatin, OR
Dr. Mohamed Abdel Khalek
M.D
Roseburg, OR
Dr. Amged Abdelaziz
MD
Portland, OR
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 Oregon 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 John Alferes, M.D.'s specialty? ▼
John Alferes, M.D. specializes in Internal Medicine Physician and practices in Portland, Oregon. Credentials: M.D..
How much does John Alferes, M.D. prescribe under Medicare Part D? ▼
In 2023, John Alferes, M.D. wrote 7,005 Medicare Part D claims totaling $303K in drug costs for 845 beneficiaries.
Where is John Alferes, M.D. located? ▼
John Alferes, M.D. is located at 3550 N INTERSTATE AVE, Portland, OR, 97227. Phone: (503) 285-9321.
What is John Alferes, M.D.'s NPI number? ▼
John Alferes, M.D.'s National Provider Identifier (NPI) is 1679680805, issued on 08/24/2006.
Does John Alferes, M.D. prescribe more brand-name or generic drugs? ▼
John Alferes, M.D.'s prescribing is 10% brand-name and 88% generic drugs by claim count, with $190K in brand drug costs.
Does John Alferes, M.D. prescribe opioids? ▼
Yes, John Alferes, M.D. had 627 opioid claims in 2023 with an opioid prescribing rate of 9.0%.
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 John Alferes, M.D. prescribe most often? ▼
Based on 2023 Medicare Part D data, John Alferes, M.D.'s most frequently prescribed drugs include Atorvastatin Calcium, Lisinopril, Amlodipine Besylate. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does John Alferes, M.D. accept Medicare? ▼
John Alferes, M.D. appears in CMS Medicare data with 7,005 Part D claims and 845 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify John Alferes, M.D.'s credentials? ▼
John Alferes, M.D.'s NPI is 1679680805 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.
- 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.