Doctor profile · Federal record

Dr. Tamer Atassi, M.D.

Gastroenterology Physician (CMS: Gastroenterology) · Joliet, IL

  • NPI 1548276819
  • Accepts Medicare
  • 33 yrs in practice
  • Male
  • Solo practice
  • No sanctions

Practice & contact

NPPES Updated May 11, 2026
Primary practice
2121 Oneida St, Suite 302
Joliet, IL 604356544
(630) 685-2877
fax (630) 395-9796
Mailing address
Po Box 433
Lemont, IL 60439

Credentials & registration

NPPES · NUCC
NPI registered
July 2006 — 20 yrs on file
Profile last updated
October 2, 2012
Year of graduation
1993 — 33 yrs since
Specialty taxonomy
207RG0100X — NUCC code
State license (1)
Illinois #036113533
Medicaid
IL #036113533

Federal sanctions & exclusions

OIG LEIE Updated May 11, 2026

No sanctions, exclusions or revocations on file

Checked against OIG LEIE on NPI 1548276819. Last verified May 11, 2026.

Medicare procedures · 2023

Top services delivered

CMS Provider Utilization
Total services
1,832
Distinct HCPCS
10
Medicare allowed
$236,457
HCPCS Description Services Patients Avg allowed
99232 Subsequent hospital care with moderate levelof medical decision making, if using time, at least 35 minutes 548 319 $81
99222 Initial hospital care with straightforward or low-level medical decision making, if using time, at least 55 minutes 240 225 $134
99214 Established patient office or other outpatient visit, 30-39 minutes 148 116 $131
43239 Biopsy of esophagus, stomach, and/or upper small bowel using a flexible endoscope 144 137 $94
99223 Initial hospital care with moderate level of medical decision making, if using time, at least 75 minutes 115 112 $179
99213 Established patient office or other outpatient visit, 20-29 minutes 103 80 $94
99204 New patient office or other outpatient visit, 45-59 minutes 98 98 $174
99233 Subsequent hospital care with moderate levelof medical decision making, if using time, at least 50 minutes 90 61 $123
45380 Biopsy of large bowel using a flexible endoscope 83 83 $176
45385 Removal of polyps or growths of large bowel using an endoscope with mechanical snare 40 40 $259

In context: peer comparison

Among 2 peers in Joliet Gastroenterology Physician, average services per provider: 125. This provider delivers 15× the peer median.

Open Payments

Industry payments received

CMS Open Payments
All-time total
$973
Transactions
29
Manufacturers
12
Payer (manufacturer) Industry Txns Amount
Abbvie INC. 14 $341.85
Conmed Corporation 1 $134.46
Boston Scientific Corporation 2 $124.36
Pinnacle Biologics, INC 1 $115.81
Takeda Pharmaceuticals U.S.A., INC. 2 $49.34
Sandoz INC. 2 $45.91
Pfizer INC. 2 $42.89
Madrigal Pharmaceuticals 1 $32.93
Janssen Biotech, INC. 1 $26.61
Salix Pharmaceuticals, A Division of Bausch Health US, LLC 1 $23.28
Evoke Pharma, INC. 1 $22.45
Phathom Pharmaceuticals, INC. 1 $13.07

By nature of payment

Food and Beverage
$973

Medicare Part D · 2023

Top prescriptions

CMS Part D Prescriber
Total claims
216
Patients
39
Total drug cost
$60,977
Drug Type Claims Patients Total cost
Omeprazole Generic 55 20 $723
Pantoprazole Sodium Generic 42 19 $607
Linzess (Linaclotide) Brand 26 0 $23,042
Dicyclomine Hcl Generic 16 0 $255
Mesalamine Generic 15 0 $11,563
Balsalazide Disodium Generic 14 0 $1,661
Budesonide Dr (Budesonide) Brand 13 0 $1,615
Trulance (Plecanatide) Brand 13 0 $20,956
Cholestyramine (Cholestyramine (With Sugar)) Brand 11 0 $442
Famotidine Generic 11 0 $113

Hospital affiliations

CMS Hospital Compare

Frequently asked questions

Auto-generated from federal data
What is Dr. Tamer Atassi's medical specialty?
Dr. Tamer Atassi practices Gastroenterology Physician in Joliet, IL.
Where does Dr. Tamer Atassi practice?
Dr. Tamer Atassi practices at 2121 Oneida St, Joliet, IL 604356544. Office phone: 6306852877.
What is Dr. Tamer Atassi's NPI?
Dr. Tamer Atassi's National Provider Identifier (NPI) is 1548276819, issued by NPPES.
Does Dr. Tamer Atassi accept Medicare assignment?
Yes. Dr. Tamer Atassi accepts Medicare assignment, meaning Medicare-allowed amounts are accepted as full payment for covered services.
What procedures does Dr. Tamer Atassi commonly perform?
Top Medicare-reported procedures in 2023: Subsequent hospital care with moderate levelof medical decision making (HCPCS 99232); Initial hospital care with straightforward or low-level medical decision making (HCPCS 99222); Established patient office or other outpatient visit (HCPCS 99214). Source: CMS Medicare Physician & Other Practitioners file.