2026 NPPES data Internal Medicine Physician NPI 1568486041 M.D.
Verify on CMS →

Heather Sung, M.D.

Internal Medicine Physician in Norwalk, Connecticut. CMS National Plan and Provider Enumeration System profile including specialty classification, practice address, and Medicare prescribing data when reported.

Federal data — no proprietary rating. PlainDoctor publishes the actual CMS NPPES and Medicare records — NPI registration, specialty, practice location, and prescribing data — without a composite score or editorial opinion on top. Every field traces to a federal source.
Prescribing volume
826
Medicare Part D claims · 67 beneficiaries · Internal Medicine Physician avg: 3K

What the federal data shows

Heather Sung, M.D. filed 826 Medicare Part D claims in 2023 as a Internal Medicine Physician in Norwalk, Connecticut.

826
Part D claims, 2023

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.

Heather Sung, M.D.'s Medicare Part D volume vs every U.S. prescriber

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

826 Top 27% higher than 73% of 1,370,886 prescribers

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. 2,000–2,200: 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.

Source CMS Medicare Part D Prescriber Public Use File · 2023

Board-eligible specialty (heuristic — not verified)

Heather Sung, 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 Heather Sung, M.D.?

Quality data not reported

NPI registry status

Active

Issued 07/27/2006

NPI 1568486041

Primary specialty

Internal Medicine Physician

High-volume

172,858 US NPIs in this specialty

Medicare Part D claims

826 70% vs specialty avg

2023 prescription claims

Specialty avg: 2,716

Specialty distribution in Connecticut

How Internal Medicine Physician compares to other specialties among Connecticut providers

Connecticut providers

Internal Medicine Physician share within Connecticut

1. Internal Medicine Physician42%2. Internal medicine21%3. Family medicine17%4. Surgical12%5. Pediatric8%
Internal Medicine Physician share within Connecticut

Specialty board-certification context

Estimated specialty board-certified rate — Internal Medicine Physician (ABMS / AOA reference)

Quality data not reported
Est. board-certified rate
78%
Internal Medicine Physician ABMS/AOA estimate

Est. board-certified rate (Internal Medicine Physician) — ABMS / AOA estimate

0%100%78%
Est. board-certified rate (Internal Medicine Physician) — ABMS / AOA estimate

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).

Heather Sung, M.D. appears in the CMS NPPES registry as a Internal Medicine Physician provider holding M.D. credentials at 128 EAST AVE, Norwalk, CT, 06851, with a listed phone of (203) 451-7212. NPI 1568486041 was issued on 07/27/2006. Because NPPES data is self-reported by the provider and refreshed monthly, the address, phone, and specialty reflect what Sung most recently submitted to CMS rather than a vetted directory listing, which is why patients should always confirm the practice is still at this location before scheduling.

Medicare Part D records for calendar year 2023 show 826 prescription claims written by this provider, covering 67 Medicare beneficiaries and totaling roughly $59K in drug spend, with an opioid prescribing rate of 12.6%. These figures capture only Medicare Part D — commercial insurance, Medicaid, and cash-pay prescriptions are not included, and any drug-beneficiary cell under 11 is suppressed by CMS for patient privacy.

Internal Medicine Physician is a high-volume specialty nationwide, with 172,858 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

128 EAST AVE
Norwalk, CT 06851

Provider Details

NPI 1568486041
Specialty Internal Medicine Physician
Credentials M.D.
Gender Female
NPI Issued 07/27/2006

Medicare Part D Prescribing Data

CMS Medicare Part D prescriber-level data for calendar year 2023.

826
Total Claims
$59K
Total Drug Cost
67
Medicare Beneficiaries

Prescribing Breakdown

30-Day Fills
955
Total Day Supply
25,549
Generic Drug Cost
$14K
Opioid Claims
104 (12.6% rate)

Patient Demographics

Average Patient Age
81.1 years
Avg HCC Risk Score
2.37
Gender Split
57% female / 43% male

Top Prescribed Drugs (Medicare Part D)

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

What Heather Sung, 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
Mirtazapine
55
Sertraline Hcl
47
Trazodone Hcl
46
Quetiapine Fumarate
42
Gabapentin
37
Midodrine Hcl
33
Omeprazole
25
Xtampza Er
Oxycodone Myristate
23
Lorazepam
22
Morphine Sulfate
22

* 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 Heather Sung, M.D. fits within the Internal Medicine Physician landscape nationally.

172,858
Internal Medicine Physician Providers in US
56
States with Internal Medicine Physician
2,716
Avg Claims per Provider

Heather Sung, M.D.'s 826 claims are below the specialty average of 2,716.

Nearby Internal Medicine Physician Providers in Connecticut

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

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 Connecticut 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 Heather Sung, M.D.'s specialty?
Heather Sung, M.D. specializes in Internal Medicine Physician and practices in Norwalk, Connecticut. Credentials: M.D..
How much does Heather Sung, M.D. prescribe under Medicare Part D?
In 2023, Heather Sung, M.D. wrote 826 Medicare Part D claims totaling $59K in drug costs for 67 beneficiaries.
Where is Heather Sung, M.D. located?
Heather Sung, M.D. is located at 128 EAST AVE, Norwalk, CT, 06851. Phone: (203) 451-7212.
What is Heather Sung, M.D.'s NPI number?
Heather Sung, M.D.'s National Provider Identifier (NPI) is 1568486041, issued on 07/27/2006.
Does Heather Sung, M.D. prescribe opioids?
Yes, Heather Sung, M.D. had 104 opioid claims in 2023 with an opioid prescribing rate of 12.6%.
How many Internal Medicine Physician providers are there in the US?
There are 172,858 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 Heather Sung, M.D. prescribe most often?
Based on 2023 Medicare Part D data, Heather Sung, M.D.'s most frequently prescribed drugs include Mirtazapine, Sertraline Hcl, Trazodone Hcl. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does Heather Sung, M.D. accept Medicare?
Heather Sung, M.D. appears in CMS Medicare data with 826 Part D claims and 67 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify Heather Sung, M.D.'s credentials?
Heather Sung, M.D.'s NPI is 1568486041 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

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