Doctor profile · Federal record
Dr. William Karnes, MD
Gastroenterology Physician (CMS: Internal Medicine) · Orange, CA
- NPI 1881652998
- Accepts Medicare
- MIPS 91.2 / 100 · 2023
- 44 yrs in practice
- Male
- Solo practice
- No sanctions
Practice & contact
- Primary practice
-
101 the City Dr S Bldg 22C
Orange, CA 928683201
(888) 717-4463
fax (714) 456-8858
Credentials & registration
- NPI registered
- May 2006 — 20 yrs on file
- Profile last updated
- September 8, 2014
- Year of graduation
- 1982 — 44 yrs since
- Specialty taxonomy
- 207RG0100X — NUCC code
- State license (1)
- California #G57458
Federal sanctions & exclusions
No sanctions, exclusions or revocations on file
Checked against OIG LEIE on NPI 1881652998. Last verified May 11, 2026.Medicare procedures · 2023
Top services delivered
Total services
962
Distinct HCPCS
10
Medicare allowed
$146,476
| HCPCS | Description | Services | Patients | Avg allowed | |
|---|---|---|---|---|---|
45385 |
Removal of polyps or growths of large bowel using an endoscope with mechanical snare | 150 | 149 | $267 | |
99214 |
Established patient office or other outpatient visit, 30-39 minutes | 140 | 124 | $140 | |
43239 |
Biopsy of esophagus, stomach, and/or upper small bowel using a flexible endoscope | 137 | 135 | $109 | |
99204 |
New patient office or other outpatient visit, 45-59 minutes | 96 | 96 | $182 | |
45380 |
Biopsy of large bowel using a flexible endoscope | 84 | 84 | $107 | |
43235 |
Diagnostic exam of esophagus, stomach, and/or upper small bowel using a flexible endoscope | 48 | 47 | $105 | |
99442 |
Telephone medical discussion with physician, 11-20 minutes | 46 | 44 | $98 | |
G0105 |
Colorectal cancer screening; colonoscopy on individual at high risk | 40 | 40 | $194 | |
91110 |
Imaging of digestive tract done from the inside of the digestive tract | 39 | 38 | $121 | |
99443 |
Telephone medical discussion with physician, 21-30 minutes | 34 | 33 | $136 |
In context: peer comparison
Among 16 peers in Orange Gastroenterology Physician, average services per provider: 65. This provider delivers 15× the peer median.Medicare Part D · 2023
Top prescriptions
Total claims
1,104
Patients
519
Total drug cost
$177,047
| Drug | Type | Claims | Patients | Total cost |
|---|---|---|---|---|
| Peg 3350-Electrolyte (Sodium Chloride/Nahco3/Kcl/Peg) | Brand | 295 | 280 | $6,576 |
| Omeprazole | Generic | 252 | 103 | $7,932 |
| Famotidine | Generic | 132 | 43 | $6,804 |
| Pantoprazole Sodium | Generic | 112 | 37 | $2,060 |
| Linzess (Linaclotide) | Brand | 62 | 28 | $88,146 |
| Sucralfate | Generic | 43 | 13 | $16,921 |
| Gavilyte-C (Peg3350/Sod Sulf,Bicarb,Cl/Kcl) | Brand | 31 | 0 | $683 |
| Ondansetron Odt (Ondansetron) | Brand | 31 | 15 | $1,590 |
| Dicyclomine Hcl | Generic | 27 | 0 | $1,554 |
| Lubiprostone | Generic | 23 | 0 | $5,412 |
Frequently asked questions
What is Dr. William Karnes's medical specialty?
Dr. William Karnes practices Gastroenterology Physician in Orange, CA.
Where does Dr. William Karnes practice?
Dr. William Karnes practices at 101 the City Dr S Bldg 22C, Orange, CA 928683201. Office phone: 8887174463.
What is Dr. William Karnes's NPI?
Dr. William Karnes's National Provider Identifier (NPI) is 1881652998, issued by NPPES.
Does Dr. William Karnes accept Medicare assignment?
Yes. Dr. William Karnes accepts Medicare assignment, meaning Medicare-allowed amounts are accepted as full payment for covered services.
What procedures does Dr. William Karnes commonly perform?
Top Medicare-reported procedures in 2023: Removal of polyps or growths of large bowel using an endoscope with mechanical snare (HCPCS 45385); Established patient office or other outpatient visit (HCPCS 99214); Biopsy of esophagus, stomach, and/or upper small bowel using a flexible endoscope (HCPCS 43239). Source: CMS Medicare Physician & Other Practitioners file.