Doctor profile · Federal record

Dr. Ammar Hassan, D.O.

Gastroenterology Physician (CMS: Gastroenterology) · Internal Medicine Physician · Internal Medicine Physician · Gastroenterology Physician · Munster, IN

  • NPI 1023428877
  • Accepts Medicare
  • 12 yrs in practice
  • Licensed in 2 states
  • Male
  • Group practice
  • No sanctions

Practice & contact

Operates at 2 locations .

NPPES Updated May 11, 2026
Primary practice
9410 Calumet Ave Ste 401
Munster, IN 463210018
(219) 922-4900
fax (219) 836-9922
Additional location
500 S Weber RD
Romeoville, IL 604466528
(815) 773-7732

Credentials & registration

NPPES · NUCC
NPI registered
May 2014 — 12 yrs on file
Profile last updated
December 15, 2025
Year of graduation
2014 — 12 yrs since
Specialty taxonomy
207RG0100X — NUCC code
State licenses (3)
Indiana #2005989A · Indiana #02005989A · Illinois #036153911

Federal sanctions & exclusions

OIG LEIE Updated May 11, 2026

No sanctions, exclusions or revocations on file

Checked against OIG LEIE on NPI 1023428877. Last verified May 11, 2026.

Medicare procedures · 2023

Top services delivered

CMS Provider Utilization
Total services
1,634
Distinct HCPCS
10
Medicare allowed
$164,109
HCPCS Description Services Patients Avg allowed
99232 Subsequent hospital care with moderate levelof medical decision making, if using time, at least 35 minutes 398 194 $73
99213 Established patient office or other outpatient visit, 20-29 minutes 185 152 $83
99222 Initial hospital care with straightforward or low-level medical decision making, if using time, at least 55 minutes 173 160 $119
99231 Subsequent hospital care with straightforward or low level of medical decision making, per day, if using time, at least 25 minutes 149 137 $44
43239 Biopsy of esophagus, stomach, and/or upper small bowel using a flexible endoscope 141 131 $76
45380 Biopsy of large bowel using a flexible endoscope 98 95 $108
99214 Established patient office or other outpatient visit, 30-39 minutes 92 79 $116
99203 New patient office or other outpatient visit, 30-44 minutes 84 84 $104
45385 Removal of polyps or growths of large bowel using an endoscope with mechanical snare 80 79 $222
43235 Diagnostic exam of esophagus, stomach, and/or upper small bowel using a flexible endoscope 40 39 $100

In context: peer comparison

Among 6 peers in this city , average services per provider: 77. This provider delivers 21× the peer median.

Open Payments

Industry payments received

CMS Open Payments
All-time total
$897
Transactions
45
Manufacturers
10
Payer (manufacturer) Industry Txns Amount
ABBVIE INC. 12 $179.70
Takeda Pharmaceuticals U.S.A., Inc. 9 $163.75
Olympus America Inc. 3 $148.05
Janssen Biotech, Inc. 8 $136.60
Ardelyx, Inc. 4 $100.06
Phathom Pharmaceuticals, Inc. 4 $72.49
Celgene Corporation 2 $36.05
Lilly USA, LLC 1 $22.37
Salix Pharmaceuticals, a division of Bausch Health US, LLC 1 $20.08
PFIZER INC. 1 $18.08

By nature of payment

Food and Beverage
$897

Medicare Part D · 2023

Top prescriptions

CMS Part D Prescriber
Total claims
879
Patients
491
Total drug cost
$164,383
Drug Type Claims Patients Total cost
Pantoprazole Sodium Generic 297 120 $4,629
Peg 3350-Electrolyte (Sodium Chloride/Nahco3/Kcl/Peg) Brand 125 123 $2,516
Gavilyte-G (Peg3350/Sod Sulf,bicarb,cl/Kcl) Brand 76 75 $1,209
Famotidine Generic 63 22 $932
Omeprazole Generic 58 23 $585
Clenpiq (Sod Picosulf/Mag Ox/Citric Ac) Brand 54 53 $9,671
Hydrocortisone Generic 35 30 $677
Dicyclomine Hcl Generic 32 17 $697
Sucralfate Generic 26 14 $2,632
Linzess (Linaclotide) Brand 22 0 $20,798

Hospital affiliations

CMS Hospital Compare

Frequently asked questions

Auto-generated from federal data
What is Dr. Ammar Hassan's medical specialty?
Dr. Ammar Hassan practices Gastroenterology Physician in Munster, IN.
Where does Dr. Ammar Hassan practice?
Dr. Ammar Hassan practices at 9410 Calumet Ave Ste 401, Munster, IN 463210018. Office phone: 2199224900.
What is Dr. Ammar Hassan's NPI?
Dr. Ammar Hassan's National Provider Identifier (NPI) is 1023428877, issued by NPPES.
Does Dr. Ammar Hassan accept Medicare assignment?
Yes. Dr. Ammar Hassan accepts Medicare assignment, meaning Medicare-allowed amounts are accepted as full payment for covered services.
What procedures does Dr. Ammar Hassan commonly perform?
Top Medicare-reported procedures in 2023: Subsequent hospital care with moderate levelof medical decision making (HCPCS 99232); Established patient office or other outpatient visit (HCPCS 99213); Initial hospital care with straightforward or low-level medical decision making (HCPCS 99222). Source: CMS Medicare Physician & Other Practitioners file.