NPI registry status
Active
2026 NPPES data Internal Medicine Physician NPI 1518169580 MD
Verify on CMS → Ian Lam, MD
Internal Medicine Physician in Mountain View, California.
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
3K
Medicare Part D claims · 337 beneficiaries · Internal Medicine Physician avg: 3K
Compiled from official public sources by the PlainDoctor editorial team.
What the federal data shows
Ian Lam, MD filed 2,779 Medicare Part D claims in 2023 as an Internal Medicine Physician in Mountain View, California.
- 3K
- Part D claims, 2023
- Likely
- board-certified (heuristic)
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.
Ian Lam, MD's Medicare Part D volume vs every U.S. prescriber
Total Medicare Part D claims, 2023, across all CMS prescribers nationally
2,779 Top 12% higher than 88% 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 certification likely (heuristic, not verified)
Ian Lam, MD practices in an ABMS-board-eligible specialty and shows active CMS Medicare participation + 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 Ian Lam, MD?
Quality data not reportedPrimary specialty
Internal Medicine Physician
Medicare Part D claims
2,779 2% vs specialty avg
Specialty distribution in California
How Internal Medicine Physician compares to other specialties among California 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).
Ian Lam, MD appears in the CMS NPPES registry as an Internal Medicine Physician provider holding MD credentials at 701 E EL CAMINO REAL, Mountain View, CA, 94040, with a listed phone of (650) 934-7400. NPI 1518169580 was issued on 06/01/2007.
Medicare Part D records for calendar year 2023 show 2,779 prescription claims written by this provider, covering 337 Medicare beneficiaries and totaling roughly $300K in drug spend.
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 | 1518169580 |
|---|---|
| Specialty | Internal Medicine Physician |
| Credentials | MD |
| Gender | Male |
| NPI Issued | 06/01/2007 |
Hospital and facility affiliations
Facilities where Ian Lam, MD 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.
Sutter Bay Medical Foundation
San Jose, CA
Affiliations sourced from CMS Doctors and Clinicians National Downloadable File; hospital ratings from CMS Hospital General Information dataset (cross-referenced by facility name + state).
License & disciplinary context - California MBC 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 ~150K California medical licensees in 2023 - they are NOT specific to Ian Lam, MD. To verify Ian Lam, MD's current license status, search the MBC public license lookup directly, or check the Federation of State Medical Boards (FSMB) verification service.
576
Total board actions, California 2023
Across 556 cases
3.84
Actions per 1,000 licensees
California statewide rate
probation
Most common action type
186 cases
MBC 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 California 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.
2,779
Total Claims
$300K
Total Drug Cost
337
Medicare Beneficiaries
Prescribing Breakdown
- 30-Day Fills
- 7,125
- Total Day Supply
- 210,536
- Generic Drug Cost
- $68K
- Antibiotic Claims
- 21
Patient Demographics
- Average Patient Age
- 79.6 years
- Avg HCC Risk Score
- 2.44
- Gender Split
- 44% female / 56% male
- Age Distribution
- <65: 11, 65-74: 88, 75-84: 134, 85+: 104
Top Prescribed Drugs (Medicare Part D)
Top drugs by claim count for calendar year 2023. Based on Medicare Part D data only.
What Ian Lam, MD prescribes most
Top Medicare Part D drugs by claim count, 2023
- Calcitriol
Calcitriol
347 claims
- Amlodipine Besylate
Amlodipine Besylate
309 claims
- Losartan Potassium
Losartan Potassium
256 claims
- Furosemide
Furosemide
220 claims
- Hydralazine Hcl
Hydralazine Hcl
153 claims
- Lisinopril 135
Lisinopril
135 claims
- Metoprolol Succinate 110
Metoprolol Succinate
110 claims
- Nifedipine Er 78
Nifedipine Er
78 claims
| Drug | Claims |
|---|---|
| Calcitriol | 347 |
| Amlodipine Besylate | 309 |
| Losartan Potassium | 256 |
| Furosemide | 220 |
| Hydralazine Hcl | 153 |
| Lisinopril | 135 |
| Metoprolol Succinate | 110 |
| Nifedipine Er Nifedipine | 78 |
| Hydrochlorothiazide | 75 |
| Tamsulosin Hcl | 65 |
* 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 Ian Lam, 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
Ian Lam, MD's 2,779 claims are above the specialty average of 2,716.
Nearby Internal Medicine Physician Providers in California
Other clinicians with the same primary specialty enrolled in California, drawn from the same CMS NPPES roster as Lam.
Dr. Jacob Aaron
MD
San Francisco, CA
Dr. Alistair Aaronson
MD
Stanford, CA
Dr. Jose Abad.
MD
Sacramento, CA
Dr. Donna Abare
MD
Oakland, CA
Marce Abare
Scotts Valley, CA
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 California 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.
Healthcare Guides
Learn more about finding, verifying, and understanding healthcare providers.
How to Find a Doctor
Step-by-step guide to choosing a provider
Verify Credentials
Check NPI, board certification & license status
Medical Specialties Explained
Who treats what and how specialties differ
Understanding Medicare Claims Data
What prescribing data reveals about a provider
In-Network vs Out-of-Network
How insurance networks affect your costs
Telehealth Guide
Virtual care options and coverage in 2026
Explore California
Frequently Asked Questions
What is Ian Lam, MD's specialty? ▼
Ian Lam, MD specializes in Internal Medicine Physician and practices in Mountain View, California. Credentials: MD.
How much does Ian Lam, MD prescribe under Medicare Part D? ▼
In 2023, Ian Lam, MD wrote 2,779 Medicare Part D claims totaling $300K in drug costs for 337 beneficiaries.
Where is Ian Lam, MD located? ▼
Ian Lam, MD is located at 701 E EL CAMINO REAL, Mountain View, CA, 94040. Phone: (650) 934-7400.
What is Ian Lam, MD's NPI number? ▼
Ian Lam, MD's National Provider Identifier (NPI) is 1518169580, issued on 06/01/2007.
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 Ian Lam, MD prescribe most often? ▼
Based on 2023 Medicare Part D data, Ian Lam, MD's most frequently prescribed drugs include Calcitriol, Amlodipine Besylate, Losartan Potassium. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does Ian Lam, MD accept Medicare? ▼
Ian Lam, MD appears in CMS Medicare data with 2,779 Part D claims and 337 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify Ian Lam, MD's credentials? ▼
Ian Lam, MD's NPI is 1518169580 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.
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.