Doctor profile · Federal record

Dr. William Marsteller, M.D.

Gastroenterology Physician (CMS: Gastroenterology) · Student in an Organized Health Care Education/Training Program · Charleston, SC

  • NPI 1992917504
  • Accepts Medicare
  • MIPS 82.4 / 100 · 2023
  • 20 yrs in practice
  • Male
  • Group practice
  • No sanctions

Practice & contact

NPPES Updated May 11, 2026
Primary practice
1962 Charlie Hall Blvd.
Charleston, SC 29414
(843) 722-8000
fax (843) 647-6066
Mailing address
2001 2Nd Ave Ste 101
Summerville, SC 294867887

Credentials & registration

NPPES · NUCC
NPI registered
May 2007 — 19 yrs on file
Profile last updated
May 7, 2020
Year of graduation
2006 — 20 yrs since
Specialty taxonomy
207RG0100X — NUCC code
State license (1)
South Carolina #32824
Medicaid
SC #GP0680

Federal sanctions & exclusions

OIG LEIE Updated May 11, 2026

No sanctions, exclusions or revocations on file

Checked against OIG LEIE on NPI 1992917504. Last verified May 11, 2026.

Medicare procedures · 2023

Top services delivered

CMS Provider Utilization
Total services
1,304
Distinct HCPCS
10
Medicare allowed
$169,122
HCPCS Description Services Patients Avg allowed
99214 Established patient office or other outpatient visit, 30-39 minutes 337 263 $118
45380 Biopsy of large bowel using a flexible endoscope 226 226 $92
43239 Biopsy of esophagus, stomach, and/or upper small bowel using a flexible endoscope 181 172 $82
45385 Removal of polyps or growths of large bowel using an endoscope with mechanical snare 173 169 $228
99204 New patient office or other outpatient visit, 45-59 minutes 129 129 $155
99232 Subsequent hospital care with moderate levelof medical decision making, if using time, at least 35 minutes 57 24 $75
43450 Dilation of esophagus 43 43 $37
76705 Limited ultrasound scan of abdomen 34 30 $55
99223 Initial hospital care with moderate level of medical decision making, if using time, at least 75 minutes 22 22 $165
74177 Ct scan of abdomen and pelvis with contrast 21 21 $210

In context: peer comparison

Among 10 peers in this city , average services per provider: 75. This provider delivers 17× the peer median.

Open Payments

Industry payments received

CMS Open Payments
All-time total
$189
Transactions
4
Manufacturers
4
Payer (manufacturer) Industry Txns Amount
Madrigal Pharmaceuticals 1 $142.48
Intercept Pharmaceuticals, Inc. 1 $16.59
Sandoz Inc. 1 $15.33
Merck Sharp & Dohme LLC 1 $14.99

By nature of payment

Food and Beverage
$189

Medicare Part D · 2023

Top prescriptions

CMS Part D Prescriber
Total claims
1,527
Patients
629
Total drug cost
$131,173
Drug Type Claims Patients Total cost
Pantoprazole Sodium Generic 419 144 $6,211
Omeprazole Generic 268 94 $4,289
Famotidine Generic 185 64 $2,991
Sod Sulf-Potass Sulf-Mag Sulf (Sodium, Potassium,mag Sulfates) Brand 116 111 $8,957
Sucralfate Generic 59 28 $2,988
Dexlansoprazole Dr (Dexlansoprazole) Brand 58 12 $20,262
Linzess (Linaclotide) Brand 57 17 $55,971
Rabeprazole Sodium Generic 55 16 $2,752
Colestipol Hcl Generic 48 16 $6,515
Promethazine Hcl Generic 47 0 $296

Hospital affiliations

CMS Hospital Compare

Frequently asked questions

Auto-generated from federal data
What is Dr. William Marsteller's medical specialty?
Dr. William Marsteller practices Gastroenterology Physician in Charleston, SC.
Where does Dr. William Marsteller practice?
Dr. William Marsteller practices at 1962 Charlie Hall Blvd., Charleston, SC 29414. Office phone: 8437228000.
What is Dr. William Marsteller's NPI?
Dr. William Marsteller's National Provider Identifier (NPI) is 1992917504, issued by NPPES.
Does Dr. William Marsteller accept Medicare assignment?
Yes. Dr. William Marsteller accepts Medicare assignment, meaning Medicare-allowed amounts are accepted as full payment for covered services.
What procedures does Dr. William Marsteller commonly perform?
Top Medicare-reported procedures in 2023: Established patient office or other outpatient visit (HCPCS 99214); Biopsy of large bowel using a flexible endoscope (HCPCS 45380); Biopsy of esophagus, stomach, and/or upper small bowel using a flexible endoscope (HCPCS 43239). Source: CMS Medicare Physician & Other Practitioners file.