2026 NPPES data Internal Medicine Physician NPI 1205985157 M.D.
Verify on CMS →

Richard Siebert, M.D.

Internal Medicine Physician in Lake Forest, 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 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
998
Medicare Part D claims · 167 beneficiaries · Internal Medicine Physician avg: 3K
Generic prescribing
82%
generic claims · 16% brand-name · higher generic rates reduce patient out-of-pocket costs

What the federal data shows

Richard Siebert, M.D. filed 998 Medicare Part D claims in 2023 as an Internal Medicine Physician in Lake Forest, Illinois, prescribing 82% generic.

998
Part D claims, 2023
82%
generic prescribing
≥75th
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.

Richard Siebert, M.D.'s Medicare Part D volume vs every U.S. prescriber

Total Medicare Part D claims, 2023, across all CMS prescribers nationally

998 ≥ 75th percentile 75% of 1,370,886 prescribers are in lower value bands

0–200: 670,926 prescribers (49%). Below this entry. 200–400: 182,923 prescribers (13%). Below this entry. 400–600: 90,619 prescribers (7%). Below this entry. 600–800: 56,224 prescribers (4%). Below this entry. 800–1,000: 40,919 prescribers (3%). This entry sits in this band. 1,000–1,200: 31,827 prescribers (2%). Above this entry. 1,200–1,400: 26,224 prescribers (2%). Above this entry. 1,400–1,600: 21,710 prescribers (2%). Above this entry. 1,600–1,800: 19,072 prescribers (1%). Above this entry. 1,800–2,000: 16,451 prescribers (1%). Above this entry. 2K+: 213,991 prescribers (16%). Above this entry. This provider 0 2K+ every Part D prescriber (claims/yr), bucketed by value

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)

Richard Siebert, 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 Richard Siebert, M.D.?

Quality data not reported

NPI registry status

Active

Issued 01/09/2007

NPI 1205985157

Primary specialty

Internal Medicine Physician

High-volume

172,737 US NPIs in this specialty

Medicare Part D claims

998 63% vs specialty avg

2023 prescription claims

Specialty avg: 2,716

Specialty distribution in Illinois

How Internal Medicine Physician compares to other specialties among Illinois providers

Illinois providers
Clinical Social Worker5.2%Physical Therapist5%Mental Health Counselor4.5%Speech-Language Pathologist4.2%Student in an Organized Heal…4.2%Pharmacist4.1%Internal Medicine Physician3.6%
Largest specialties in Illinois (% of in-state 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).

Richard Siebert, M.D. appears in the CMS NPPES registry as an Internal Medicine Physician provider holding M.D. credentials at 700 N WESTMORELAND RD, Lake Forest, IL, 60045, with a listed phone of (847) 234-8808. NPI 1205985157 was issued on 01/09/2007.

Medicare Part D records for calendar year 2023 show 998 prescription claims written by this provider, covering 167 Medicare beneficiaries and totaling roughly $32K in drug spend, split 16% brand-name and 82% generic by claim count.

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

700 N WESTMORELAND RD
Lake Forest, IL 60045

Provider Details

NPI 1205985157
Specialty Internal Medicine Physician
Credentials M.D.
Gender Male
NPI Issued 01/09/2007

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 Richard Siebert, M.D.. To verify Richard Siebert, M.D.'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 · Typical

Richard Siebert, M.D. - brand share 16.0%
Internal Medicine Physician average

16% brand-name claims vs 82% generic, on 998 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.

998
Total Claims
$32K
Total Drug Cost
167
Medicare Beneficiaries

Prescribing Breakdown

30-Day Fills
2,840
Total Day Supply
84,231
Brand vs Generic
16% brand / 82% generic
Brand Drug Cost
$16K
Generic Drug Cost
$16K
Antibiotic Claims
19

Patient Demographics

Average Patient Age
77.8 years
Avg HCC Risk Score
0.93
Gender Split
60% female / 40% male

Top Prescribed Drugs (Medicare Part D)

Top drugs by claim count for calendar year 2023. Based on Medicare Part D data only.

What Richard Siebert, M.D. prescribes most

Top Medicare Part D drugs by claim count, 2023

claims
Source CMS Medicare Part D Prescriber Public Use File As of 2023
Drug Claims
Levothyroxine Sodium
158
Hydrochlorothiazide
78
Atorvastatin Calcium
77
Losartan Potassium
72
Synthroid
Levothyroxine Sodium
68
Amlodipine Besylate
62
Lisinopril
58
Atenolol
43
Metformin Hcl
34
Rosuvastatin 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 Richard Siebert, 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

Richard Siebert, M.D.'s 998 claims are below the specialty average of 2,716.

Nearby Internal Medicine Physician Providers in Illinois

Other clinicians with the same primary specialty enrolled in Illinois, drawn from the same CMS NPPES roster as Siebert.

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 Illinois 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.

Frequently Asked Questions

What is Richard Siebert, M.D.'s specialty?
Richard Siebert, M.D. specializes in Internal Medicine Physician and practices in Lake Forest, Illinois. Credentials: M.D..
How much does Richard Siebert, M.D. prescribe under Medicare Part D?
In 2023, Richard Siebert, M.D. wrote 998 Medicare Part D claims totaling $32K in drug costs for 167 beneficiaries.
Where is Richard Siebert, M.D. located?
Richard Siebert, M.D. is located at 700 N WESTMORELAND RD, Lake Forest, IL, 60045. Phone: (847) 234-8808.
What is Richard Siebert, M.D.'s NPI number?
Richard Siebert, M.D.'s National Provider Identifier (NPI) is 1205985157, issued on 01/09/2007.
Does Richard Siebert, M.D. prescribe more brand-name or generic drugs?
Richard Siebert, M.D.'s prescribing is 16% brand-name and 82% generic drugs by claim count, with $16K in brand drug costs.
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 Richard Siebert, M.D. prescribe most often?
Based on 2023 Medicare Part D data, Richard Siebert, M.D.'s most frequently prescribed drugs include Levothyroxine Sodium, Hydrochlorothiazide, Atorvastatin Calcium. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does Richard Siebert, M.D. accept Medicare?
Richard Siebert, M.D. appears in CMS Medicare data with 998 Part D claims and 167 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify Richard Siebert, M.D.'s credentials?
Richard Siebert, M.D.'s NPI is 1205985157 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

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.