NPI registry status
Active
2026 NPPES data Internal Medicine Physician NPI 1295782241 M.D.
Verify on CMS → Mark Lamos, M.D.
Internal Medicine Physician in Hunt Valley, Maryland.
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
978
Medicare Part D claims · 185 beneficiaries · Internal Medicine Physician avg: 3K
Generic prescribing
83%
generic claims · 15% 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
Mark Lamos, M.D. filed 978 Medicare Part D claims in 2023 as an Internal Medicine Physician in Hunt Valley, Maryland, prescribing 83% generic.
- 978
- Part D claims, 2023
- 83%
- 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.
Mark Lamos, M.D.'s Medicare Part D volume vs every U.S. prescriber
Total Medicare Part D claims, 2023, across all CMS prescribers nationally
978 Top 25% higher than 75% 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)
Mark Lamos, 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 Mark Lamos, M.D.?
Quality data not reportedPrimary specialty
Internal Medicine Physician
Medicare Part D claims
978 64% vs specialty avg
Specialty distribution in Maryland
How Internal Medicine Physician compares to other specialties among Maryland 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).
Mark Lamos, M.D. appears in the CMS NPPES registry as an Internal Medicine Physician provider holding M.D. credentials at 9 SCHILLING RD, Hunt Valley, MD, 21031, with a listed phone of (410) 771-9220. NPI 1295782241 was issued on 05/27/2006.
Medicare Part D records for calendar year 2023 show 978 prescription claims written by this provider, covering 185 Medicare beneficiaries and totaling roughly $81K in drug spend, split 15% brand-name and 83% generic by claim count, with an opioid prescribing rate of 2.2%.
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 | 1295782241 |
|---|---|
| Specialty | Internal Medicine Physician |
| Credentials | M.D. |
| Gender | Male |
| NPI Issued | 05/27/2006 |
Brand vs generic prescribing mix · Typical
Mark Lamos, M.D. - brand share 15.0%
Internal Medicine Physician average
15% brand-name claims vs 83% generic, on 978 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.
978
Total Claims
$81K
Total Drug Cost
185
Medicare Beneficiaries
Prescribing Breakdown
- 30-Day Fills
- 1,663
- Total Day Supply
- 45,436
- Brand vs Generic
- 15% brand / 83% generic
- Brand Drug Cost
- $67K
- Generic Drug Cost
- $13K
- Opioid Claims
- 22 (2.2% rate)
- Antibiotic Claims
- 52
Patient Demographics
- Average Patient Age
- 72.9 years
- Avg HCC Risk Score
- 1.25
- Gender Split
- 58% female / 42% male
- Age Distribution
- <65: 24, 65-74: 77, 75-84: 63, 85+: 21
Top Prescribed Drugs (Medicare Part D)
Top drugs by claim count for calendar year 2023. Based on Medicare Part D data only.
What Mark Lamos, M.D. prescribes most
Top Medicare Part D drugs by claim count, 2023
- Rosuvastatin Calcium
Rosuvastatin Calcium
60 claims
- Methylprednisolone
Methylprednisolone
51 claims
- Losartan Potassium
Losartan Potassium
35 claims
- Amlodipine Besylate
Amlodipine Besylate
29 claims
- Lisinopril
Lisinopril
29 claims
- Levothyroxine Sodium
Levothyroxine Sodium
28 claims
- Furosemide
Furosemide
27 claims
- Metoprolol Succinate 22
Metoprolol Succinate
22 claims
| Drug | Claims |
|---|---|
| Rosuvastatin Calcium | 60 |
| Methylprednisolone | 51 |
| Losartan Potassium | 35 |
| Amlodipine Besylate | 29 |
| Lisinopril | 29 |
| Levothyroxine Sodium | 28 |
| Furosemide | 27 |
| Metoprolol Succinate | 22 |
| Albuterol Sulfate Hfa Albuterol Sulfate | 21 |
| Atorvastatin Calcium | 21 |
* 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 Mark Lamos, 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
Mark Lamos, M.D.'s 978 claims are below the specialty average of 2,716.
Nearby Internal Medicine Physician Providers in Maryland
Other clinicians with the same primary specialty enrolled in Maryland, drawn from the same CMS NPPES roster as Lamos.
Dr. Joshua Aaron
MD
Elkton, MD
Dr. Alina Aasim
M.D.
Baltimore, MD
Dr. Eduardo Abarca Rojas
M.D.
Parkville, MD
Dr. Rasheed Abassi
M.D.
Clinton, MD
Dr. Shastine Abate
MD
Baltimore, MD
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 Maryland 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 Mark Lamos, M.D.'s specialty? ▼
Mark Lamos, M.D. specializes in Internal Medicine Physician and practices in Hunt Valley, Maryland. Credentials: M.D..
How much does Mark Lamos, M.D. prescribe under Medicare Part D? ▼
In 2023, Mark Lamos, M.D. wrote 978 Medicare Part D claims totaling $81K in drug costs for 185 beneficiaries.
Where is Mark Lamos, M.D. located? ▼
Mark Lamos, M.D. is located at 9 SCHILLING RD, Hunt Valley, MD, 21031. Phone: (410) 771-9220.
What is Mark Lamos, M.D.'s NPI number? ▼
Mark Lamos, M.D.'s National Provider Identifier (NPI) is 1295782241, issued on 05/27/2006.
Does Mark Lamos, M.D. prescribe more brand-name or generic drugs? ▼
Mark Lamos, M.D.'s prescribing is 15% brand-name and 83% generic drugs by claim count, with $67K in brand drug costs.
Does Mark Lamos, M.D. prescribe opioids? ▼
Yes, Mark Lamos, M.D. had 22 opioid claims in 2023 with an opioid prescribing rate of 2.2%.
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 Mark Lamos, M.D. prescribe most often? ▼
Based on 2023 Medicare Part D data, Mark Lamos, M.D.'s most frequently prescribed drugs include Rosuvastatin Calcium, Methylprednisolone, Losartan Potassium. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does Mark Lamos, M.D. accept Medicare? ▼
Mark Lamos, M.D. appears in CMS Medicare data with 978 Part D claims and 185 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify Mark Lamos, M.D.'s credentials? ▼
Mark Lamos, M.D.'s NPI is 1295782241 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.
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.