Doctor profile · Federal record

Dr. Catherine Nguyen-Loh, DO

Family Medicine Physician (CMS: Family Practice) · Fountain Valley, CA

  • NPI 1558828848
  • Accepts Medicare
  • 7 yrs in practice
  • Female
  • Group practice
  • No sanctions

Practice & contact

NPPES Updated May 11, 2026
Primary practice
8970 Warner Ave
Fountain Valley, CA 927083211
(714) 477-8400
fax (714) 477-8401

Credentials & registration

NPPES · NUCC
NPI registered
February 2019 — 7 yrs on file
Profile last updated
March 5, 2024
Year of graduation
2019 — 7 yrs since
Specialty taxonomy
207Q00000X — NUCC code
State license (1)
California #20A20201

Federal sanctions & exclusions

OIG LEIE Updated May 11, 2026

No sanctions, exclusions or revocations on file

Checked against OIG LEIE on NPI 1558828848. Last verified May 11, 2026.

Medicare procedures · 2023

Top services delivered

CMS Provider Utilization
Total services
211
Distinct HCPCS
4
Medicare allowed
$24,868
HCPCS Description Services Patients Avg allowed
99213 Established patient office or other outpatient visit, 20-29 minutes 90 62 $98
99214 Established patient office or other outpatient visit, 30-39 minutes 90 55 $139
99442 Telephone medical discussion with physician, 11-20 minutes 18 16 $98
G0439 Annual wellness visit, includes a personalized prevention plan of service (pps), subsequent visit 13 13 $140

In context: peer comparison

Among 16 peers in this city , average services per provider: 78. This provider delivers 2.7× the peer median.

Open Payments

Industry payments received

CMS Open Payments
All-time total
$29
Transactions
1
Manufacturers
1
Payer (manufacturer) Industry Txns Amount
Lilly USA, LLC 1 $29.01

By nature of payment

Food and Beverage
$29

Medicare Part D · 2023

Top prescriptions

CMS Part D Prescriber
Total claims
412
Patients
138
Total drug cost
$7,823
Drug Type Claims Patients Total cost
Atorvastatin Calcium Generic 81 35 $1,469
Amlodipine Besylate Generic 40 16 $338
Levothyroxine Sodium Generic 39 18 $1,456
Losartan Potassium Generic 37 15 $731
Fluticasone Propionate Generic 33 13 $438
Gabapentin Generic 24 0 $246
Simvastatin Generic 21 0 $450
Alprazolam Generic 19 0 $167
Lisinopril Generic 18 0 $258
Metformin Hcl Generic 18 11 $356

Hospital affiliations

CMS Hospital Compare

Frequently asked questions

Auto-generated from federal data
What is Dr. Catherine Nguyen-Loh's medical specialty?
Dr. Catherine Nguyen-Loh practices Family Medicine Physician in Fountain Valley, CA.
Where does Dr. Catherine Nguyen-Loh practice?
Dr. Catherine Nguyen-Loh practices at 8970 Warner Ave, Fountain Valley, CA 927083211. Office phone: 7144778400.
What is Dr. Catherine Nguyen-Loh's NPI?
Dr. Catherine Nguyen-Loh's National Provider Identifier (NPI) is 1558828848, issued by NPPES.
Does Dr. Catherine Nguyen-Loh accept Medicare assignment?
Yes. Dr. Catherine Nguyen-Loh accepts Medicare assignment, meaning Medicare-allowed amounts are accepted as full payment for covered services.
What procedures does Dr. Catherine Nguyen-Loh commonly perform?
Top Medicare-reported procedures in 2023: Established patient office or other outpatient visit (HCPCS 99213); Established patient office or other outpatient visit (HCPCS 99214); Telephone medical discussion with physician (HCPCS 99442). Source: CMS Medicare Physician & Other Practitioners file.