2026 NPPES data Internal Medicine Physician NPI 1164869640 MD
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Karina Whelan, MD

Internal Medicine Physician in Chapel Hill, North Carolina. This profile is drawn from the federal National Provider Identifier Registry (CMS NPPES), which lists more than 7 million U.S. healthcare providers — including 172,858 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
2K
Medicare Part D claims · 168 beneficiaries · Internal Medicine Physician avg: 3K
Generic prescribing
84%
generic claims · 15% brand-name · higher generic rates reduce patient out-of-pocket costs
Compiled from official public sources by the PlainDoctor editorial team.

What the federal data shows

Karina Whelan, MD filed 2,368 Medicare Part D claims in 2023 as a Internal Medicine Physician in Chapel Hill, North Carolina, prescribing 84% generic.

2K
Part D claims, 2023
84%
generic prescribing
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.

Karina Whelan, MD's Medicare Part D volume vs every U.S. prescriber

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

2,368 Top 14% higher than 86% 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%). Below this entry. 1,000–1,200: 31,827 prescribers (2%). Below this entry. 1,200–1,400: 26,224 prescribers (2%). Below this entry. 1,400–1,600: 21,710 prescribers (2%). Below this entry. 1,600–1,800: 19,072 prescribers (1%). Below this entry. 1,800–2,000: 16,451 prescribers (1%). Below this entry. 2,000–2,200: 213,991 prescribers (16%). This entry sits in this band. 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 certification likely (heuristic — not verified)

Karina Whelan, MD practices in an ABMS-board-eligible specialty and shows active CMS Medicare participation + 2 hospital affiliations — 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 Karina Whelan, MD?

Quality data not reported

NPI registry status

Active

Issued 05/24/2013

NPI 1164869640

Primary specialty

Internal Medicine Physician

High-volume

172,858 US NPIs in this specialty

Medicare Part D claims

2,368 13% vs specialty avg

2023 prescription claims

Specialty avg: 2,716

Specialty distribution in North Carolina

How Internal Medicine Physician compares to other specialties among North Carolina providers

North Carolina providers

Largest specialties in North Carolina (% of in-state providers)

Clinical Social Worker — 7.1%Clinical Social Worker7.1%Behavior Technician — 6.4%Behavior Technician6.4%Pharmacist — 5%Pharmacist5%Student in an Organized Health Care Education/Training Program — 4.5%Student in an Organized Health Care Education/Training Program4.5%Physical Therapist — 4.3%Physical Therapist4.3%Physician Assistant — 4.2%Physician Assistant4.2%Internal Medicine Physician — 2.5%Internal Medicine Physician2.5%
Largest specialties in North Carolina (% of in-state providers)

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).

Karina Whelan, MD appears in the CMS NPPES registry as a Internal Medicine Physician provider holding MD credentials at 102 MASON FARM RD STE 3100, Chapel Hill, NC, 27599, with a listed phone of (984) 974-4462. NPI 1164869640 was issued on 05/24/2013. Because NPPES data is self-reported by the provider and refreshed monthly, the address, phone, and specialty reflect what Whelan 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 2,368 prescription claims written by this provider, covering 168 Medicare beneficiaries and totaling roughly $324K in drug spend, split 15% brand-name and 84% generic by claim count, with an opioid prescribing rate of 1.6%. 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

102 MASON FARM RD STE 3100
Chapel Hill, NC 27599

Provider Details

NPI 1164869640
Specialty Internal Medicine Physician
Credentials MD
Gender Female
NPI Issued 05/24/2013

Hospital and facility affiliations

Facilities where Karina Whelan, 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.

Legacy Healthcare Services Inc
Durham, NC
University OF North Carolina AT Chapel Hill
Chapel Hill, NC

Affiliations sourced from CMS Doctors and Clinicians National Downloadable File; hospital ratings from CMS Hospital General Information dataset (cross-referenced by facility name + state).

Brand vs generic prescribing mix · Typical

Karina Whelan, MD — brand share 15.0%
Internal Medicine Physician average

15% brand-name claims vs 84% generic, on 2,368 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.

2,368
Total Claims
$324K
Total Drug Cost
168
Medicare Beneficiaries

Prescribing Breakdown

30-Day Fills
5,560
Total Day Supply
163,980
Brand vs Generic
15% brand / 84% generic
Brand Drug Cost
$273K
Generic Drug Cost
$48K
Opioid Claims
37 (1.6% rate)
Antibiotic Claims
22

Patient Demographics

Average Patient Age
72.5 years
Avg HCC Risk Score
1.55
Gender Split
77% female / 23% male

Top Prescribed Drugs (Medicare Part D)

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

What Karina Whelan, MD 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
Rosuvastatin Calcium
127
Atorvastatin Calcium
120
Levothyroxine Sodium
109
Losartan Potassium
82
Metoprolol Succinate
74
Gabapentin
68
Amlodipine Besylate
66
Omeprazole
65
Lisinopril
64
Duloxetine Hcl
63

* 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 Karina Whelan, MD 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

Karina Whelan, MD's 2,368 claims are below the specialty average of 2,716.

Nearby Internal Medicine Physician Providers in North Carolina

Other clinicians with the same primary specialty enrolled in North Carolina, drawn from the same CMS NPPES roster as Whelan.

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 North Carolina 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 Karina Whelan, MD's specialty?
Karina Whelan, MD specializes in Internal Medicine Physician and practices in Chapel Hill, North Carolina. Credentials: MD.
How much does Karina Whelan, MD prescribe under Medicare Part D?
In 2023, Karina Whelan, MD wrote 2,368 Medicare Part D claims totaling $324K in drug costs for 168 beneficiaries.
Where is Karina Whelan, MD located?
Karina Whelan, MD is located at 102 MASON FARM RD STE 3100, Chapel Hill, NC, 27599. Phone: (984) 974-4462.
What is Karina Whelan, MD's NPI number?
Karina Whelan, MD's National Provider Identifier (NPI) is 1164869640, issued on 05/24/2013.
Does Karina Whelan, MD prescribe more brand-name or generic drugs?
Karina Whelan, MD's prescribing is 15% brand-name and 84% generic drugs by claim count, with $273K in brand drug costs.
Does Karina Whelan, MD prescribe opioids?
Yes, Karina Whelan, MD had 37 opioid claims in 2023 with an opioid prescribing rate of 1.6%.
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 Karina Whelan, MD prescribe most often?
Based on 2023 Medicare Part D data, Karina Whelan, MD's most frequently prescribed drugs include Rosuvastatin Calcium, Atorvastatin Calcium, Levothyroxine Sodium. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does Karina Whelan, MD accept Medicare?
Karina Whelan, MD appears in CMS Medicare data with 2,368 Part D claims and 168 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify Karina Whelan, MD's credentials?
Karina Whelan, MD's NPI is 1164869640 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

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.