2026 NPPES data Internal Medicine Physician NPI 1821386145 M.D.
Verify on CMS →

WILLIAM BIGELOW, M.D.

Internal Medicine Physician in MOUNT PLEASANT, 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
10K
Medicare Part D claims · 663 beneficiaries · Internal Medicine Physician avg: 3K
Generic prescribing
89%
generic claims · 11% brand-name · higher generic rates reduce patient out-of-pocket costs
What the federal data reveals: WILLIAM BIGELOW, M.D. is a Internal Medicine Physician ([object Object]) practicing in MOUNT PLEASANT, South Carolina with a Medicare Part D prescribing footprint of 10K claims across 663 beneficiaries — 11% brand-name prescribing .

What stands out: WILLIAM BIGELOW, M.D. filed 9,858 Medicare Part D claims in 2023 across MOUNT PLEASANT, South Carolina. Every figure on this page comes straight from federal CMS records, with no proprietary rating applied.

Board certification likely (heuristic — not verified)

WILLIAM BIGELOW, M.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).

WILLIAM BIGELOW, M.D. at a glance

Quality data not reported

NPI registry status

Active

Issued 07/20/2011

NPI 1821386145

Primary specialty

Internal Medicine Physician

High-volume

172,858 US NPIs in this specialty

Medicare Part D claims

9,858 263% vs specialty avg

2023 prescription claims

Specialty avg: 2,716

Specialty distribution in South Carolina

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

South Carolina providers

Internal Medicine Physician share within South Carolina

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

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).

WILLIAM BIGELOW, M.D. is a Internal Medicine Physician provider practicing in MOUNT PLEASANT, South Carolina, according to the CMS National Plan and Provider Enumeration System (NPPES). Credentials: M.D.. NPI: 1821386145. 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.

WILLIAM BIGELOW, M.D. appears in the CMS NPPES registry as a Internal Medicine Physician provider holding M.D. credentials at 1113 PARKWEST BLVD, MOUNT PLEASANT, SC, 29466, with a listed phone of (843) 876-1445. NPI 1821386145 was issued on 07/20/2011. Because NPPES data is self-reported by the provider and refreshed monthly, the address, phone, and specialty reflect what BIGELOW 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 9,858 prescription claims written by this provider, covering 663 Medicare beneficiaries and totaling roughly $1.1 million in drug spend, split 11% brand-name and 89% generic by claim count, with an opioid prescribing rate of 3.8%. 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

1113 PARKWEST BLVD
MOUNT PLEASANT, SC 29466

Provider Details

NPI 1821386145
Specialty Internal Medicine Physician
Credentials M.D.
Gender Male
NPI Issued 07/20/2011

Hospital and facility affiliations

Facilities where WILLIAM BIGELOW, M.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.

CAROLINA FAMILY CARE INC
MOUNT PLEASANT, 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).

Brand vs generic prescribing mix · Typical

WILLIAM BIGELOW, M.D. — brand share 11.0%
Specialty average (est.)

11% brand-name claims vs 89% generic, on 9,858 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.

9,858
Total Claims
$1.1M
Total Drug Cost
663
Medicare Beneficiaries

Prescribing Breakdown

30-Day Fills
22,325
Total Day Supply
656,716
Brand vs Generic
11% brand / 89% generic
Brand Drug Cost
$868K
Generic Drug Cost
$198K
Opioid Claims
374 (3.8% rate)
Antibiotic Claims
82

Patient Demographics

Average Patient Age
71.4 years
Avg HCC Risk Score
1.11
Gender Split
49% female / 51% male
Age Distribution
<65: 69, 65-74: 360, 75-84: 214, 85+: 20

Top Prescribed Drugs (Medicare Part D)

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

Drug Claims
Atorvastatin Calcium
748
Amlodipine Besylate
391
Losartan Potassium
339
Lisinopril
318
Omeprazole
296
Levothyroxine Sodium
288
Rosuvastatin Calcium
241
Gabapentin
201
Metformin Hcl
192
Hydrochlorothiazide
188

* 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 WILLIAM BIGELOW, 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

WILLIAM BIGELOW, M.D.'s 9,858 claims are above the specialty average of 2,716.

Nearby Internal Medicine Physician Providers in South Carolina

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

Compare Internal Medicine Physician nationally: see state-by-state distribution →

Frequently Asked Questions

What is WILLIAM BIGELOW, M.D.'s specialty?
WILLIAM BIGELOW, M.D. specializes in Internal Medicine Physician and practices in MOUNT PLEASANT, South Carolina. Credentials: M.D..
How much does WILLIAM BIGELOW, M.D. prescribe under Medicare Part D?
In 2023, WILLIAM BIGELOW, M.D. wrote 9,858 Medicare Part D claims totaling $1.1M in drug costs for 663 beneficiaries.
Where is WILLIAM BIGELOW, M.D. located?
WILLIAM BIGELOW, M.D. is located at 1113 PARKWEST BLVD, MOUNT PLEASANT, SC, 29466. Phone: (843) 876-1445.
What is WILLIAM BIGELOW, M.D.'s NPI number?
WILLIAM BIGELOW, M.D.'s National Provider Identifier (NPI) is 1821386145, issued on 07/20/2011.
Does WILLIAM BIGELOW, M.D. prescribe more brand-name or generic drugs?
WILLIAM BIGELOW, M.D.'s prescribing is 11% brand-name and 89% generic drugs by claim count, with $868K in brand drug costs.
Does WILLIAM BIGELOW, M.D. prescribe opioids?
Yes, WILLIAM BIGELOW, M.D. had 374 opioid claims in 2023 with an opioid prescribing rate of 3.8%.
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 WILLIAM BIGELOW, M.D. prescribe most often?
Based on 2023 Medicare Part D data, WILLIAM BIGELOW, M.D.'s most frequently prescribed drugs include Atorvastatin Calcium, Amlodipine Besylate, Losartan Potassium. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does WILLIAM BIGELOW, M.D. accept Medicare?
WILLIAM BIGELOW, M.D. appears in CMS Medicare data with 9,858 Part D claims and 663 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify WILLIAM BIGELOW, M.D.'s credentials?
WILLIAM BIGELOW, M.D.'s NPI is 1821386145 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