Doctor profile · Federal record

Dr. Mason Shieh, M.D., M.B.A.

Emergency Medicine Physician (CMS: Emergency Medicine) · Los Alamitos, CA

  • NPI 1467718486
  • Accepts Medicare
  • MIPS 86.3 / 100 · 2023
  • 14 yrs in practice
  • Male
  • Group practice
  • No sanctions

Practice & contact

Operates at 2 locations .

NPPES Updated May 11, 2026
Primary practice
3751 Katella Ave
Los Alamitos, CA 907203113
(714) 456-8888
Additional location
1115 S Sunset Ave
West Covina, CA 917903940
(626) 962-4011
Mailing address
1115 S Sunset Ave
West Covina, CA 917903940

Credentials & registration

NPPES · NUCC
NPI registered
April 2012 — 14 yrs on file
Profile last updated
April 2, 2025
Year of graduation
2012 — 14 yrs since
Specialty taxonomy
207P00000X — NUCC code
State license (1)
California #A134394

Federal sanctions & exclusions

OIG LEIE Updated May 11, 2026

No sanctions, exclusions or revocations on file

Checked against OIG LEIE on NPI 1467718486. Last verified May 11, 2026.

Medicare procedures · 2023

Top services delivered

CMS Provider Utilization
Total services
350
Distinct HCPCS
4
Medicare allowed
$50,905
HCPCS Description Services Patients Avg allowed
99285 Emergency department visit with high level of medical decision making 160 157 $184
93010 Routine electrocardiogram (ecg) using at least 12 leads with interpretation and report only 72 68 $9
99284 Emergency department visit with moderate level of medical decision making 59 58 $127
99291 Critical care, first 30-74 minutes 59 58 $226

In context: peer comparison

Among 10 peers in Los Alamitos Emergency Medicine Physician, average services per provider: 84. This provider delivers 4.2× the peer median.

Medicare Part D · 2023

Top prescriptions

CMS Part D Prescriber
Total claims
197
Patients
193
Total drug cost
$1,290
Drug Type Claims Patients Total cost
Cephalexin Generic 48 48 $362
Hydrocodone-Acetaminophen (Hydrocodone/Acetaminophen) Brand 34 34 $146
Ondansetron Odt (Ondansetron) Brand 31 31 $297
Amoxicillin-Clavulanate Potass (Amoxicillin/Potassium Clav) Brand 18 16 $205
Meclizine Hcl Generic 17 17 $59
Prednisone Generic 14 13 $44
Metronidazole Generic 12 11 $114
Tramadol Hcl Generic 12 12 $24
Acetaminophen-Codeine (Acetaminophen With Codeine) Brand 11 11 $38

Hospital affiliations

CMS Hospital Compare

Frequently asked questions

Auto-generated from federal data
What is Dr. Mason Shieh's medical specialty?
Dr. Mason Shieh practices Emergency Medicine Physician in Los Alamitos, CA.
Where does Dr. Mason Shieh practice?
Dr. Mason Shieh practices at 3751 Katella Ave, Los Alamitos, CA 907203113. Office phone: 7144568888.
What is Dr. Mason Shieh's NPI?
Dr. Mason Shieh's National Provider Identifier (NPI) is 1467718486, issued by NPPES.
Does Dr. Mason Shieh accept Medicare assignment?
Yes. Dr. Mason Shieh accepts Medicare assignment, meaning Medicare-allowed amounts are accepted as full payment for covered services.
What procedures does Dr. Mason Shieh commonly perform?
Top Medicare-reported procedures in 2023: Emergency department visit with high level of medical decision making (HCPCS 99285); Routine electrocardiogram (ecg) using at least 12 leads with interpretation and report only (HCPCS 93010); Emergency department visit with moderate level of medical decision making (HCPCS 99284). Source: CMS Medicare Physician & Other Practitioners file.