2026 NPPES data Nephrology Physician NPI 1922395037 MD PH,D.
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BLAITHIN MCMAHON, MD PH,D.

Nephrology Physician in CHARLESTON, South Carolina. 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
251
Medicare Part D claims · 60 beneficiaries · Nephrology Physician avg: 1K
Generic prescribing
89%
generic claims · 11% brand-name · higher generic rates reduce patient out-of-pocket costs
Industry payments
$1.6K
10 payments · CMS Open Payments (Sunshine Act)
What the federal data reveals: BLAITHIN MCMAHON, MD PH,D. is a Nephrology Physician ([object Object]) practicing in CHARLESTON, South Carolina with a Medicare Part D prescribing footprint of 251 claims across 60 beneficiaries — 11% brand-name prescribing . Industry payments of $1.6K across 10 transactions are disclosed under CMS Open Payments (Sunshine Act).

What stands out: BLAITHIN MCMAHON, MD PH,D. filed 251 Medicare Part D claims in 2023 across CHARLESTON, South Carolina. Every figure on this page comes straight from federal CMS records, with no proprietary rating applied.

Board certification likely (heuristic — not verified)

BLAITHIN MCMAHON, MD PH,D. practices in an ABMS-board-eligible specialty and shows active CMS Medicare participation + 1 hospital affiliation — signals consistent with board-certified status. For verified board certification, see CertificationMatters.org (the official ABMS public lookup).

BLAITHIN MCMAHON, MD PH,D. at a glance

Quality data not reported

NPI registry status

Active

Issued 07/10/2011

NPI 1922395037

Primary specialty

Nephrology Physician

Mid-sized

10,534 US NPIs in this specialty

Medicare Part D claims

251 83% vs specialty avg

2023 prescription claims

Specialty avg: 1,454

Specialty distribution in South Carolina

How Nephrology Physician compares to other specialties among South Carolina providers

South Carolina providers

Nephrology Physician share within South Carolina

1. Nephrology Physician42%2. Internal medicine21%3. Family medicine17%4. Surgical12%5. Pediatric8%
Nephrology Physician share within South Carolina

Specialty board-certification context

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

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

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

0%100%78%
Est. board-certified rate (Nephrology 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).

BLAITHIN MCMAHON, MD PH,D. is a Nephrology Physician provider practicing in CHARLESTON, South Carolina, according to the CMS National Plan and Provider Enumeration System (NPPES). Credentials: MD PH,D.. NPI: 1922395037. This profile includes practice location, specialty classification, and organizational affiliations from the CMS provider registry. Provider information is self-reported to CMS and updated monthly.

BLAITHIN MCMAHON, MD PH,D. appears in the CMS NPPES registry as a Nephrology Physician provider holding MD PH,D. credentials at 171 ASHLEY AVE, CHARLESTON, SC, 29425, with a listed phone of (843) 792-1414. NPI 1922395037 was issued on 07/10/2011. Because NPPES data is self-reported by the provider and refreshed monthly, the address, phone, and specialty reflect what MCMAHON 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 251 prescription claims written by this provider, covering 60 Medicare beneficiaries and totaling roughly $20K in drug spend, split 11% brand-name and 89% generic by claim count. 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.

Nephrology Physician is a mid-sized specialty nationwide, with 10,534 enrolled providers across 55 states and an average of 1,454 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

171 ASHLEY AVE
CHARLESTON, SC 29425

Provider Details

NPI 1922395037
Specialty Nephrology Physician
Credentials MD PH,D.
Gender Female
NPI Issued 07/10/2011

Hospital and facility affiliations

Facilities where BLAITHIN MCMAHON, MD PH,D. 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.

UNIVERSITY MEDICAL ASSOCIATES OF THE MEDICAL UNIVERSITY OF SOUTH CAROL
CHARLESTON, SC

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

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 BLAITHIN MCMAHON, MD PH,D.. Source: openpaymentsdata.cms.gov.

Total received

$1.6K

Largest payer

Baxter Healthcare

Most common payment type

Food and Beverage

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

BLAITHIN MCMAHON, MD PH,D. — brand share 11.0%
Specialty average (est.)

11% brand-name claims vs 89% generic, on 251 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.

251
Total Claims
$20K
Total Drug Cost
60
Medicare Beneficiaries

Prescribing Breakdown

30-Day Fills
533
Total Day Supply
15,818
Brand vs Generic
11% brand / 89% generic
Brand Drug Cost
$13K
Generic Drug Cost
$7K

Patient Demographics

Average Patient Age
71.8 years
Avg HCC Risk Score
2.44
Gender Split
48% female / 52% male

Top Prescribed Drugs (Medicare Part D)

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

Drug Claims
Losartan Potassium
33
Furosemide
22
Tamsulosin Hcl
22
Calcitriol
20
Amlodipine Besylate
15
Vitamin D2
Ergocalciferol (Vitamin D2)
14
Isosorbide Mononitrate Er
Isosorbide Mononitrate
12
Jardiance
Empagliflozin
12
Potassium Chloride
11

* Counts below 11 are suppressed by CMS for patient privacy. Generic names shown where available from CMS Part D data.

Nephrology Physician Overview

How BLAITHIN MCMAHON, MD PH,D. fits within the Nephrology Physician landscape nationally.

10,534
Nephrology Physician Providers in US
55
States with Nephrology Physician
1,454
Avg Claims per Provider

BLAITHIN MCMAHON, MD PH,D.'s 251 claims are below the specialty average of 1,454.

Nearby Nephrology Physician Providers in South Carolina

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

Compare Nephrology Physician nationally: see state-by-state distribution →

Frequently Asked Questions

What is BLAITHIN MCMAHON, MD PH,D.'s specialty?
BLAITHIN MCMAHON, MD PH,D. specializes in Nephrology Physician and practices in CHARLESTON, South Carolina. Credentials: MD PH,D..
How much does BLAITHIN MCMAHON, MD PH,D. prescribe under Medicare Part D?
In 2023, BLAITHIN MCMAHON, MD PH,D. wrote 251 Medicare Part D claims totaling $20K in drug costs for 60 beneficiaries.
Where is BLAITHIN MCMAHON, MD PH,D. located?
BLAITHIN MCMAHON, MD PH,D. is located at 171 ASHLEY AVE, CHARLESTON, SC, 29425. Phone: (843) 792-1414.
What is BLAITHIN MCMAHON, MD PH,D.'s NPI number?
BLAITHIN MCMAHON, MD PH,D.'s National Provider Identifier (NPI) is 1922395037, issued on 07/10/2011.
Does BLAITHIN MCMAHON, MD PH,D. prescribe more brand-name or generic drugs?
BLAITHIN MCMAHON, MD PH,D.'s prescribing is 11% brand-name and 89% generic drugs by claim count, with $13K in brand drug costs.
How many Nephrology Physician providers are there in the US?
There are 10,534 Nephrology Physician providers across 55 states in the US. The average Nephrology Physician provider writes 1,454 Medicare Part D claims per year.
What drugs does BLAITHIN MCMAHON, MD PH,D. prescribe most often?
Based on 2023 Medicare Part D data, BLAITHIN MCMAHON, MD PH,D.'s most frequently prescribed drugs include Losartan Potassium, Furosemide, Tamsulosin Hcl. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does BLAITHIN MCMAHON, MD PH,D. accept Medicare?
BLAITHIN MCMAHON, MD PH,D. appears in CMS Medicare data with 251 Part D claims and 60 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify BLAITHIN MCMAHON, MD PH,D.'s credentials?
BLAITHIN MCMAHON, MD PH,D.'s NPI is 1922395037 with credentials MD PH,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