Doctor profile · Federal record

Dr. Yesim Yilmaz Demirdag, M.D.

Allergy & Immunology Physician (CMS: Allergy/Immunology) · Irvine, CA

  • NPI 1134330921
  • Accepts Medicare
  • MIPS 91.2 / 100 · 2023
  • 36 yrs in practice
  • Female
  • Group practice
  • No sanctions

Practice & contact

NPPES Updated May 11, 2026
Primary practice
821 Health Sciences RD Medical Sciences I C-240
Irvine, CA 926979214
(949) 824-5818
Mailing address
Po Box 9214, West Virginia University
Morgantown, WV 265069214

Credentials & registration

NPPES · NUCC
NPI registered
May 2007 — 19 yrs on file
Profile last updated
August 27, 2020
Year of graduation
1990 — 36 yrs since
Specialty taxonomy
207K00000X — NUCC code
State license (1)
California #C166841
Medicaid
LA #07225

Federal sanctions & exclusions

OIG LEIE Updated May 11, 2026

No sanctions, exclusions or revocations on file

Checked against OIG LEIE on NPI 1134330921. Last verified May 11, 2026.

Medicare procedures · 2023

Top services delivered

CMS Provider Utilization
Total services
563
Distinct HCPCS
10
Medicare allowed
$43,284
HCPCS Description Services Patients Avg allowed
95004 Test for allergy using allergenic extract 203 11 $5
99214 Established patient office or other outpatient visit, 30-39 minutes 97 71 $105
99215 Established patient office or other outpatient visit, 40-54 minutes 73 57 $151
99214 Established patient office or other outpatient visit, 30-39 minutes 47 33 $103
99213 Established patient office or other outpatient visit, 20-29 minutes 29 26 $70
99204 New patient office or other outpatient visit, 45-59 minutes 24 24 $143
99215 Established patient office or other outpatient visit, 40-54 minutes 20 17 $154
95076 Test for allergy using ingested items, initial 2 hours 18 18 $79
99205 New patient office or other outpatient visit, 60-74 minutes 18 18 $194
94016 Test to measure expiratory airflow and volume initiated by patient and evaluated by provider 17 16 $26

In context: peer comparison

Among 3 peers in Irvine Allergy & Immunology Physician, average services per provider: 51. This provider delivers 11× the peer median.

Open Payments

Industry payments received

CMS Open Payments
All-time total
$3,090
Transactions
9
Manufacturers
5
Payer (manufacturer) Industry Txns Amount
Csl Behring 3 $2,768.05
Grifols USA, LLC 1 $167.42
Regeneron Healthcare Solutions, INC. 3 $109.36
Genentech USA, INC. 1 $23.21
Pharming Healthcare, INC. 1 $21.95

By nature of payment

Consulting Fee
$2,609
Food and Beverage
$448
Travel and Lodging
$33

Medicare Part D · 2023

Top prescriptions

CMS Part D Prescriber
Total claims
505
Patients
85
Total drug cost
$665,731
Drug Type Claims Patients Total cost
Fluticasone Propionate Generic 92 31 $2,170
Azelastine Hcl Generic 48 20 $2,028
Incruse Ellipta (Umeclidinium Bromide) Brand 36 0 $13,984
Olopatadine Hcl Generic 34 0 $3,691
Xolair (Omalizumab) Brand 34 0 $76,845
Ipratropium Bromide Generic 32 14 $2,147
Dupixent Pen (Dupilumab) Brand 31 0 $121,656
Hizentra (Immun Glob G(Igg)/Pro/Iga 0-50) Brand 31 0 $316,133
Montelukast Sodium Generic 30 0 $722
Dupixent Syringe (Dupilumab) Brand 27 0 $102,893

Frequently asked questions

Auto-generated from federal data
What is Dr. Yesim Yilmaz Demirdag's medical specialty?
Dr. Yesim Yilmaz Demirdag practices Allergy & Immunology Physician in Irvine, CA.
Where does Dr. Yesim Yilmaz Demirdag practice?
Dr. Yesim Yilmaz Demirdag practices at 821 Health Sciences RD Medical Sciences I C-240, Irvine, CA 926979214. Office phone: 9498245818.
What is Dr. Yesim Yilmaz Demirdag's NPI?
Dr. Yesim Yilmaz Demirdag's National Provider Identifier (NPI) is 1134330921, issued by NPPES.
Does Dr. Yesim Yilmaz Demirdag accept Medicare assignment?
Yes. Dr. Yesim Yilmaz Demirdag accepts Medicare assignment, meaning Medicare-allowed amounts are accepted as full payment for covered services.
What procedures does Dr. Yesim Yilmaz Demirdag commonly perform?
Top Medicare-reported procedures in 2023: Test for allergy using allergenic extract (HCPCS 95004); Established patient office or other outpatient visit (HCPCS 99214); Established patient office or other outpatient visit (HCPCS 99215). Source: CMS Medicare Physician & Other Practitioners file.