Doctor profile · Federal record

Dr. Mark O'Brien, MD

Family Medicine Physician (CMS: Family Practice) · Preventive Medicine/Occupational Environmental Medicine Physician · Carmel, IN

  • NPI 1124129267
  • Accepts Medicare
  • 38 yrs in practice
  • Male
  • Group practice
  • No sanctions

Practice & contact

Operates at 2 locations .

NPPES Updated May 11, 2026
Primary practice
11725 N Illinois St Ste 250
Carmel, IN 460323015
(317) 688-5300
fax (317) 688-5313
Additional location
409 E Washington St
Butler, IN 467211175
(260) 868-5843
fax (260) 868-5844
Mailing address
250 N Shadeland Ave
Indianapolis, IN 462194959

Credentials & registration

NPPES · NUCC
NPI registered
September 2006 — 20 yrs on file
Profile last updated
January 6, 2021
Year of graduation
1988 — 38 yrs since
Specialty taxonomy
207Q00000X — NUCC code
State license (1)
Indiana #01037757A
Medicaid
IN #200033390

Federal sanctions & exclusions

OIG LEIE Updated May 11, 2026

No sanctions, exclusions or revocations on file

Checked against OIG LEIE on NPI 1124129267. Last verified May 11, 2026.

Medicare procedures · 2023

Top services delivered

CMS Provider Utilization
Total services
745
Distinct HCPCS
9
Medicare allowed
$77,829
HCPCS Description Services Patients Avg allowed
99214 Established patient office or other outpatient visit, 30-39 minutes 458 238 $118
99213 Established patient office or other outpatient visit, 20-29 minutes 86 77 $83
G0008 Administration of influenza virus vaccine 51 51 $29
90662 Influenza vaccine split virus, preservative free 50 50 $70
90677 Pneumococcal conjugate vaccine, 20 valent (pcv20), for intramuscular use 29 29 $271
G0009 Administration of pneumococcal vaccine 27 27 $29
81003 Automated urinalysis test 19 16 $2
83036 Hemoglobin a1c level 14 14 $10
99496 Transitional care management services for problem of high complexity 11 11 $257

In context: peer comparison

Among 18 peers in this city , average services per provider: 66. This provider delivers 11× the peer median.

Medicare Part D · 2023

Top prescriptions

CMS Part D Prescriber
Total claims
2,938
Patients
864
Total drug cost
$41,276
Drug Type Claims Patients Total cost
Atorvastatin Calcium Generic 626 174 $8,410
Amlodipine Besylate Generic 311 98 $1,780
Losartan Potassium Generic 285 87 $3,955
Levothyroxine Sodium Generic 239 63 $3,881
Metoprolol Succinate Generic 232 63 $5,551
Lisinopril Generic 216 66 $1,462
Hydrochlorothiazide Generic 176 49 $705
Metformin Hcl Er (Metformin Hcl) Brand 166 52 $1,281
Omeprazole Generic 151 42 $1,549
Tamsulosin Hcl Generic 127 41 $3,130

Frequently asked questions

Auto-generated from federal data
What is Dr. Mark O'Brien's medical specialty?
Dr. Mark O'Brien practices Family Medicine Physician in Carmel, IN.
Where does Dr. Mark O'Brien practice?
Dr. Mark O'Brien practices at 11725 N Illinois St Ste 250, Carmel, IN 460323015. Office phone: 3176885300.
What is Dr. Mark O'Brien's NPI?
Dr. Mark O'Brien's National Provider Identifier (NPI) is 1124129267, issued by NPPES.
Does Dr. Mark O'Brien accept Medicare assignment?
Yes. Dr. Mark O'Brien accepts Medicare assignment, meaning Medicare-allowed amounts are accepted as full payment for covered services.
What procedures does Dr. Mark O'Brien commonly perform?
Top Medicare-reported procedures in 2023: Established patient office or other outpatient visit (HCPCS 99214); Established patient office or other outpatient visit (HCPCS 99213); Administration of influenza virus vaccine (HCPCS G0008). Source: CMS Medicare Physician & Other Practitioners file.