NPI registry status
Active
2026 NPPES data Geriatric Medicine (Internal Medicine) Physician NPI 1881627446 MD
Verify on CMS → Herbert Sier, MD
Geriatric Medicine (Internal Medicine) Physician in Chicago, Illinois.
This profile is drawn from the federal National Provider Identifier Registry (CMS NPPES), which lists more than 7 million U.S. healthcare providers - including 4,171 in Geriatric Medicine (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
22
Medicare Part D claims · Geriatric Medicine (Internal Medicine) Physician avg: 4K
Generic prescribing
0%
generic claims · 95% 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
Herbert Sier, MD filed 22 Medicare Part D claims in 2023 as a Geriatric Medicine (Internal Medicine) Physician in Chicago, Illinois, prescribing 0% generic.
- 22
- Part D claims, 2023
- 0%
- generic prescribing
- ≥0th
- pct by Part D claim volume (lower-bound band)
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.
Federal trust snapshot
What official records show about Herbert Sier, MD
Federal records show an active NPI with Medicare Part D prescribing activity — verifiable registry data, not a proprietary rating.
- Verified
NPI registry status
Active listing in the CMS National Provider Identifier Registry (NPI 1881627446), first enumerated 07/08/2006.
Source: CMS NPPES
- Reported
Medicare Part D participation
Filed 22 Medicare Part D prescription claims in the 2023 CMS public use file — indicates active Medicare prescribing participation.
Source: CMS Part D Prescriber PUF
- Reported
Board certification signal
Practices in an ABMS-board-eligible specialty; board certification not confirmed in federal records.
- State context
State board disciplinary context
Illinois statewide board action statistics are published annually — these figures describe aggregate state activity, not Herbert Sier, MD's individual license status. Verify directly with the state medical board.
Source: IDFPR annual report 2023
- Not in federal data
Individual sanction lookup
PlainDoctor does not publish per-provider disciplinary determinations. Confirm current license and any individual actions through the state medical board or FSMB verification service.
Source: State medical board / FSMB
This trust snapshot summarizes only what appears in federal CMS/NPPES public records. It is not a composite score, star rating, patient review, or clinical recommendation. PlainDoctor never fabricates reviews or AggregateRating schema.
CMS NPPES provider registry desk
NPI 1881627446 · Geriatric Medicine (Internal Medicine) Physician
NPI-10 · ENUM-LEGACY · TAX-NARROW · RX-TRACE · BOOK-THIN · PHOTO-ENUM
- NPI-10 1881627446
- ENUM-LEGACY 2006
- TAX-NARROW 4,171
- RX-TRACE 22
- BOOK-THIN 157 in Illinois
- PHOTO-ENUM Eugenia Pritchett · 2006
Herbert Sier, MD's Medicare Part D volume vs every U.S. prescriber
Total Medicare Part D claims, 2023, across all CMS prescribers nationally
22 ≥ 0th percentile 0% of 1,370,886 prescribers are in lower value bands
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.
The percentile is a conservative 100-claim band: it counts only prescribers in lower claim-volume bands. Medicare Part D claim volume is activity context, not a quality measure or recommendation. See methodology § corpus placement.
Source CMS Medicare Part D Prescriber Public Use File · 2023
◑
Board-eligible specialty (heuristic, not verified)
Herbert Sier, 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 Herbert Sier, MD?
Quality data not reportedPrimary specialty
Geriatric Medicine (Internal Medicine) Physician
Medicare Part D claims
22 100% vs specialty avg
Specialty distribution in Illinois
How Geriatric Medicine (Internal Medicine) Physician compares to other specialties among Illinois 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 Geriatric Medicine (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).
Practice Address
Provider Details
| NPI | 1881627446 |
|---|---|
| Specialty | Geriatric Medicine (Internal Medicine) Physician |
| Credentials | MD |
| Gender | Male |
| NPI Issued | 07/08/2006 |
License & disciplinary context - Illinois IDFPR 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 ~42K Illinois medical licensees in 2023 - they are NOT specific to Herbert Sier, MD. To verify Herbert Sier, MD's current license status, search the IDFPR public license lookup directly, or check the Federation of State Medical Boards (FSMB) verification service.
106
Total board actions, Illinois 2023
Across 103 cases
2.52
Actions per 1,000 licensees
Illinois statewide rate
probation
Most common action type
38 cases
IDFPR 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 Illinois disciplinary trends page. Cross-checked against FSMB U.S. Medical Regulatory Trends.
Brand vs generic prescribing mix · Brand-heavy
Herbert Sier, MD - brand share 95.0%
Geriatric Medicine (Internal Medicine) Physician average
95% brand-name claims vs 0% generic, on 22 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.
22
Total Claims
$31K
Total Drug Cost
N/A
Medicare Beneficiaries
Prescribing Breakdown
- 30-Day Fills
- 66
- Total Day Supply
- 1,980
- Brand vs Generic
- 95% brand / 0% generic
- Brand Drug Cost
- $31K
Patient Demographics
- Average Patient Age
- 75.0 years
- Avg HCC Risk Score
- 0.98
More Geriatric Medicine (Internal Medicine) Physician in IL →
All providers in Illinois →
Compare specialties →
Geriatric Medicine (Internal Medicine) Physician Overview
How Herbert Sier, MD fits within the Geriatric Medicine (Internal Medicine) Physician landscape nationally.
4,171
Geriatric Medicine (Internal Medicine) Physician Providers in US
52
States with Geriatric Medicine (Internal Medicine) Physician
4,450
Avg Claims per Provider
Herbert Sier, MD's 22 claims are below the specialty average of 4,450.
Nationwide Geriatric Medicine (Internal Medicine) Physician peers with similar MIPS or enrollment year
Two federal-record peer sets for Sier, both outside Illinois so the neighborhoods are not geographic containment.
Same NPPES enumeration year (2006)
Same-specialty clinicians who entered the NPI registry in the same calendar year, outside this state.
Nearby Geriatric Medicine (Internal Medicine) Physician Providers in Illinois
Other clinicians with the same primary specialty enrolled in Illinois, drawn from the same CMS NPPES roster as Sier.
One of 157 Geriatric Medicine (Internal Medicine) Physician providers enrolled in Illinois, 5 are shown here.
Frequently Asked Questions
What is Herbert Sier, MD's specialty? ▼
Herbert Sier, MD specializes in Geriatric Medicine (Internal Medicine) Physician and practices in Chicago, Illinois. Credentials: MD.
How much does Herbert Sier, MD prescribe under Medicare Part D? ▼
In 2023, Herbert Sier, MD wrote 22 Medicare Part D claims totaling $31K in drug costs for N/A beneficiaries.
Where is Herbert Sier, MD located? ▼
Herbert Sier, MD is located at 680 N LAKE SHORE DR, Chicago, IL, 60611. Phone: (312) 695-9797.
What is Herbert Sier, MD's NPI number? ▼
Herbert Sier, MD's National Provider Identifier (NPI) is 1881627446, issued on 07/08/2006.
Does Herbert Sier, MD prescribe more brand-name or generic drugs? ▼
Herbert Sier, MD's prescribing is 95% brand-name and 0% generic drugs by claim count, with $31K in brand drug costs.
How many Geriatric Medicine (Internal Medicine) Physician providers are there in the US? ▼
There are 4,171 Geriatric Medicine (Internal Medicine) Physician providers across 52 states in the US. The average Geriatric Medicine (Internal Medicine) Physician provider writes 4,450 Medicare Part D claims per year.
Does Herbert Sier, MD accept Medicare? ▼
Herbert Sier, MD appears in CMS Medicare data with 22 Part D claims and N/A Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify Herbert Sier, MD's credentials? ▼
Herbert Sier, MD's NPI is 1881627446 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.