NPI registry status
Active
2026 NPPES data Allergy & Immunology Physician NPI 1659341311 M.D.
Verify on CMS → Sang Chyung, M.D.
Allergy & Immunology Physician in Michigan City, Indiana.
This profile is drawn from the federal National Provider Identifier Registry (CMS NPPES), which lists more than 7 million U.S. healthcare providers - including 3,390 in Allergy & Immunology 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
366
Medicare Part D claims · 61 beneficiaries · Allergy & Immunology Physician avg: 764
Generic prescribing
84%
generic claims · 16% brand-name · higher generic rates reduce patient out-of-pocket costs
Industry payments
$53.86
3 payments · CMS Open Payments (Sunshine Act)
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
Sang Chyung, M.D. filed 366 Medicare Part D claims in 2023 as a Allergy & Immunology Physician in Michigan City, Indiana, prescribing 84% generic.
- 366
- Part D claims, 2023
- 84%
- generic prescribing
- $53.86
- industry payments (Sunshine Act)
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.
Sang Chyung, M.D.'s Medicare Part D volume vs every U.S. prescriber
Total Medicare Part D claims, 2023, across all CMS prescribers nationally
366 Top 43% higher than 57% 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)
Sang Chyung, 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 Sang Chyung, M.D.?
Quality data not reportedPrimary specialty
Allergy & Immunology Physician
Medicare Part D claims
366 52% vs specialty avg
Specialty distribution in Indiana
How Allergy & Immunology Physician compares to other specialties among Indiana 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 Allergy & Immunology 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).
Sang Chyung, M.D. appears in the CMS NPPES registry as a Allergy & Immunology Physician provider holding M.D. credentials at 1225 E COOLSPRING AVE, Michigan City, IN, 46360, with a listed phone of (219) 878-5038. NPI 1659341311 was issued on 01/25/2006.
Medicare Part D records for calendar year 2023 show 366 prescription claims written by this provider, covering 61 Medicare beneficiaries and totaling roughly $30K in drug spend, split 16% brand-name and 84% generic by claim count.
Allergy & Immunology Physician is a narrow specialty nationwide, with 3,390 enrolled providers across 52 states and an average of 764 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 | 1659341311 |
|---|---|
| Specialty | Allergy & Immunology Physician |
| Credentials | M.D. |
| Gender | Female |
| NPI Issued | 01/25/2006 |
Industry payments received (2024) - CMS Open Payments transparency data
The federal Physician Payments Sunshine Act (part of the Affordable Care Act) requires drug and medical-device manufacturers + group purchasing organizations to publicly report payments and other transfers of value to physicians and teaching hospitals. The data below covers 2024 for Sang Chyung, M.D.. Source: openpaymentsdata.cms.gov.
Total received
$54
Largest payer
PFIZER INC.
Most common payment type
Education
Industry payments are not necessarily indicators of bias, they include research funding, consulting fees for evidence-based work, royalties for inventions, food at conferences, and similar items. The disclosure exists for transparency. Read our methodology for how we interpret this data.
Brand vs generic prescribing mix · Typical
Sang Chyung, M.D. - brand share 16.0%
Allergy & Immunology Physician average
16% brand-name claims vs 84% generic, on 366 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.
366
Total Claims
$30K
Total Drug Cost
61
Medicare Beneficiaries
Prescribing Breakdown
- 30-Day Fills
- 679
- Total Day Supply
- 17,328
- Brand vs Generic
- 16% brand / 84% generic
- Brand Drug Cost
- $24K
- Generic Drug Cost
- $7K
- Antibiotic Claims
- 92
Patient Demographics
- Average Patient Age
- 73.3 years
- Avg HCC Risk Score
- 1.01
- Gender Split
- 70% female / 30% male
Top Prescribed Drugs (Medicare Part D)
Top drugs by claim count for calendar year 2023. Based on Medicare Part D data only.
What Sang Chyung, M.D. prescribes most
Top Medicare Part D drugs by claim count, 2023
- Montelukast Sodium
Montelukast Sodium
97 claims
- Azithromycin 31
Azithromycin
31 claims
- Prednisone 28
Prednisone
28 claims
- Azelastine Hcl 21
Azelastine Hcl
21 claims
- Amoxicillin-Clavul… 19
Amoxicillin-Clavulanate Potass
19 claims
- Fluticasone Propio… 17
Fluticasone Propionate
17 claims
- Arnuity Ellipta 16
Arnuity Ellipta
16 claims
- Doxycycline Hyclate 15
Doxycycline Hyclate
15 claims
| Drug | Claims |
|---|---|
| Montelukast Sodium | 97 |
| Azithromycin | 31 |
| Prednisone | 28 |
| Azelastine Hcl | 21 |
| Amoxicillin-Clavulanate Potass Amoxicillin/Potassium Clav | 19 |
| Fluticasone Propionate | 17 |
| Arnuity Ellipta Fluticasone Furoate | 16 |
| Doxycycline Hyclate | 15 |
| Pulmicort Flexhaler Budesonide | 11 |
* Counts below 11 are suppressed by CMS for patient privacy. Generic names shown where available from CMS Part D data.
Allergy & Immunology Physician Overview
How Sang Chyung, M.D. fits within the Allergy & Immunology Physician landscape nationally.
3,390
Allergy & Immunology Physician Providers in US
52
States with Allergy & Immunology Physician
764
Avg Claims per Provider
Sang Chyung, M.D.'s 366 claims are below the specialty average of 764.
Nearby Allergy & Immunology Physician Providers in Indiana
Other clinicians with the same primary specialty enrolled in Indiana, drawn from the same CMS NPPES roster as Chyung.
Dr. Muhammad Afzal
M.D.
New Castle, IN
Dr. Sohaib Aleem
MD
South Bend, IN
Dr. Frank Amodio
MD
Evansville, IN
Dr. Christina Barnes
MD
South Bend, IN
Dr. Jillian Belmonte
MD
Indianapolis, IN
Compare Allergy & Immunology 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 Indiana medical board, federal registration is not a license check. Credential verification guide
- Weigh a second option: compare this provider with a nearby Allergy & Immunology 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 Indiana
Frequently Asked Questions
What is Sang Chyung, M.D.'s specialty? ▼
Sang Chyung, M.D. specializes in Allergy & Immunology Physician and practices in Michigan City, Indiana. Credentials: M.D..
How much does Sang Chyung, M.D. prescribe under Medicare Part D? ▼
In 2023, Sang Chyung, M.D. wrote 366 Medicare Part D claims totaling $30K in drug costs for 61 beneficiaries.
Where is Sang Chyung, M.D. located? ▼
Sang Chyung, M.D. is located at 1225 E COOLSPRING AVE, Michigan City, IN, 46360. Phone: (219) 878-5038.
What is Sang Chyung, M.D.'s NPI number? ▼
Sang Chyung, M.D.'s National Provider Identifier (NPI) is 1659341311, issued on 01/25/2006.
Does Sang Chyung, M.D. prescribe more brand-name or generic drugs? ▼
Sang Chyung, M.D.'s prescribing is 16% brand-name and 84% generic drugs by claim count, with $24K in brand drug costs.
How many Allergy & Immunology Physician providers are there in the US? ▼
There are 3,390 Allergy & Immunology Physician providers across 52 states in the US. The average Allergy & Immunology Physician provider writes 764 Medicare Part D claims per year.
What drugs does Sang Chyung, M.D. prescribe most often? ▼
Based on 2023 Medicare Part D data, Sang Chyung, M.D.'s most frequently prescribed drugs include Montelukast Sodium, Azithromycin, Prednisone. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does Sang Chyung, M.D. accept Medicare? ▼
Sang Chyung, M.D. appears in CMS Medicare data with 366 Part D claims and 61 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify Sang Chyung, M.D.'s credentials? ▼
Sang Chyung, M.D.'s NPI is 1659341311 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.