Doctor profile · Federal record
Dr. Jonathan Williamson, M.D.
Gastroenterology Physician (CMS: Gastroenterology) · Hartford, CT
- NPI 1881891703
- Accepts Medicare
- MIPS 83.2 / 100 · 2023
- 19 yrs in practice
- Male
- Group practice
- No sanctions
Practice & contact
- Primary practice
-
85 Seymour St, Suite 1000
Hartford, CT 061065501
(860) 246-2571
fax (860) 246-3691 - Mailing address
-
30 Waterchase Dr
Rocky Hill, CT 060672110
Credentials & registration
- NPI registered
- July 2007 — 19 yrs on file
- Profile last updated
- January 4, 2019
- Year of graduation
- 2007 — 19 yrs since
- Specialty taxonomy
- 207RG0100X — NUCC code
- State license (1)
- Connecticut #052966
- Medicaid
- CT #008052313
Federal sanctions & exclusions
No sanctions, exclusions or revocations on file
Checked against OIG LEIE on NPI 1881891703. Last verified May 11, 2026.Medicare procedures · 2023
Top services delivered
Total services
409
Distinct HCPCS
10
Medicare allowed
$52,268
| HCPCS | Description | Services | Patients | Avg allowed | |
|---|---|---|---|---|---|
45380 |
Biopsy of large bowel using a flexible endoscope | 59 | 58 | $125 | |
43239 |
Biopsy of esophagus, stomach, and/or upper small bowel using a flexible endoscope | 58 | 57 | $82 | |
99222 |
Initial hospital care with straightforward or low-level medical decision making, if using time, at least 55 minutes | 54 | 53 | $134 | |
99232 |
Subsequent hospital care with moderate levelof medical decision making, if using time, at least 35 minutes | 47 | 39 | $83 | |
99213 |
Established patient office or other outpatient visit, 20-29 minutes | 40 | 33 | $96 | |
99214 |
Established patient office or other outpatient visit, 30-39 minutes | 39 | 35 | $135 | |
45385 |
Removal of polyps or growths of large bowel using an endoscope with mechanical snare | 36 | 34 | $265 | |
74328 |
Review by radiologist of image from tube placement into bile duct using an endoscope | 25 | 18 | $24 | |
43237 |
Ultrasound exam of esophagus, stomach, and/or upper small bowel using a flexible endoscope through mouth | 17 | 17 | $192 | |
43264 |
Removal of stone or debris from bile or pancreatic duct using a flexible endoscope | 12 | 12 | $211 |
In context: peer comparison
Among 9 peers in Hartford Gastroenterology Physician, average services per provider: 35. This provider delivers 12× the peer median.Open Payments
Industry payments received
All-time total
$1,914
Transactions
80
Manufacturers
15
| Payer (manufacturer) | Industry | Txns | Amount |
|---|---|---|---|
| Abbvie INC. | 19 | $411.99 | |
| Takeda Pharmaceuticals U.S.A., INC. | 11 | $305.28 | |
| Janssen Biotech, INC. | 13 | $280.97 | |
| Salix Pharmaceuticals, A Division of Bausch Health US, LLC | 10 | $216.79 | |
| Genzyme Corporation | 7 | $197.06 | |
| Lilly USA, LLC | 4 | $88.23 | |
| Ironwood Pharmaceuticals, INC | 3 | $78.99 | |
| Regeneron Healthcare Solutions, INC. | 3 | $73.45 | |
| Mallinckrodt Hospital Products INC. | 2 | $47.01 | |
| Intercept Pharmaceuticals, INC. | 2 | $42.76 | |
| Vibrant Gastro, INC. | 1 | $36.90 | |
| Gilead Sciences, INC. | 2 | $34.62 | |
| Celgene Corporation | 1 | $27.60 | |
| Pentax of America, INC. | 1 | $25.02 | |
| Sandoz INC. | 1 | $24.97 |
By nature of payment
Medicare Part D · 2023
Top prescriptions
Total claims
650
Patients
220
Total drug cost
$113,972
| Drug | Type | Claims | Patients | Total cost |
|---|---|---|---|---|
| Pantoprazole Sodium | Generic | 176 | 45 | $2,557 |
| Omeprazole | Generic | 170 | 64 | $3,530 |
| Sod Sulf-Potass Sulf-Mag Sulf (Sodium, Potassium,Mag Sulfates) | Brand | 71 | 70 | $5,908 |
| Sucralfate | Generic | 50 | 13 | $7,363 |
| Lubiprostone | Generic | 41 | 12 | $12,051 |
| Linzess (Linaclotide) | Brand | 36 | 0 | $24,644 |
| Famotidine | Generic | 30 | 0 | $921 |
| Lansoprazole | Generic | 21 | 0 | $2,079 |
| Creon (Lipase/Protease/Amylase) | Brand | 19 | 0 | $53,127 |
| Gavilyte-G (Peg3350/Sod Sulf,Bicarb,Cl/Kcl) | Brand | 19 | 16 | $290 |
Frequently asked questions
What is Dr. Jonathan Williamson's medical specialty?
Dr. Jonathan Williamson practices Gastroenterology Physician in Hartford, CT.
Where does Dr. Jonathan Williamson practice?
Dr. Jonathan Williamson practices at 85 Seymour St, Hartford, CT 061065501. Office phone: 8602462571.
What is Dr. Jonathan Williamson's NPI?
Dr. Jonathan Williamson's National Provider Identifier (NPI) is 1881891703, issued by NPPES.
Does Dr. Jonathan Williamson accept Medicare assignment?
Yes. Dr. Jonathan Williamson accepts Medicare assignment, meaning Medicare-allowed amounts are accepted as full payment for covered services.
What procedures does Dr. Jonathan Williamson commonly perform?
Top Medicare-reported procedures in 2023: 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); Initial hospital care with straightforward or low-level medical decision making (HCPCS 99222). Source: CMS Medicare Physician & Other Practitioners file.