Doctor profile · Federal record

Dr. Woo Sung Ahn, MD

Internal Medicine Physician (CMS: Internal Medicine) · Lakewood, CA

  • NPI 1396807806
  • Accepts Medicare
  • 50 yrs in practice
  • Male
  • Group practice
  • No sanctions

Practice & contact

NPPES Updated May 11, 2026
Primary practice
20145 S Pioneer Blvd
Lakewood, CA 907151051
(562) 916-5020
fax (562) 916-5022

Credentials & registration

NPPES · NUCC
NPI registered
December 2006 — 20 yrs on file
Profile last updated
July 8, 2007
Year of graduation
1976 — 50 yrs since
Specialty taxonomy
207R00000X — NUCC code
State license (1)
California #A51408

Federal sanctions & exclusions

OIG LEIE Updated May 11, 2026

No sanctions, exclusions or revocations on file

Checked against OIG LEIE on NPI 1396807806. Last verified May 11, 2026.

Medicare procedures · 2023

Top services delivered

CMS Provider Utilization
Total services
679
Distinct HCPCS
7
Medicare allowed
$51,951
HCPCS Description Services Patients Avg allowed
99213 Established patient office or other outpatient visit, 20-29 minutes 432 102 $100
36415 Insertion of needle into vein for collection of blood sample 157 90 $8
G0439 Annual wellness visit, includes a personalized prevention plan of service (pps), subsequent visit 32 32 $144
99442 Telephone medical discussion with physician, 11-20 minutes 19 15 $100
90686 Influenza vaccine, quadrivalent, preservative free, 0.5 ml dosage 13 13 $22
93000 Routine electrocardiogram (ecg) using at least 12 leads with interpretation and report 13 11 $16
G0008 Administration of influenza virus vaccine 13 13 $30

In context: peer comparison

Among 7 peers in Lakewood Internal Medicine Physician, average services per provider: 89. This provider delivers 7.6× the peer median.

Open Payments

Industry payments received

CMS Open Payments
All-time total
$793
Transactions
39
Manufacturers
10
Payer (manufacturer) Industry Txns Amount
Novo Nordisk INC 12 $175.23
Amgen INC. 4 $90.95
Sumitomo Pharma America, INC. 3 $88.10
Abbvie INC. 4 $87.28
Aimmune Therapeutics, INC. 4 $83.77
Boehringer Ingelheim Pharmaceuticals, INC. 3 $79.61
Radius Health, INC. 3 $74.17
Bayer Healthcare Pharmaceuticals INC. 3 $56.01
AstraZeneca Pharmaceuticals Lp 2 $36.37
GlaxoSmithKline, LLC. 1 $21.88

By nature of payment

Food and Beverage
$793

Medicare Part D · 2023

Top prescriptions

CMS Part D Prescriber
Total claims
8,188
Patients
1,980
Total drug cost
$1,405,089
Drug Type Claims Patients Total cost
Atorvastatin Calcium Generic 1,142 300 $18,932
Rosuvastatin Calcium Generic 996 279 $32,912
Losartan-Hydrochlorothiazide (Losartan/Hydrochlorothiazide) Brand 736 180 $14,888
Amlodipine Besylate Generic 703 166 $7,608
Losartan Potassium Generic 593 150 $8,859
Clopidogrel (Clopidogrel Bisulfate) Brand 528 134 $8,171
Vascepa (Icosapent Ethyl) Brand 518 111 $340,143
Metformin Hcl ER (Metformin Hcl) Brand 507 120 $7,879
Glipizide ER (Glipizide) Brand 461 105 $12,456
Icosapent Ethyl Generic 398 87 $222,748

Frequently asked questions

Auto-generated from federal data
What is Dr. Woo Sung Ahn's medical specialty?
Dr. Woo Sung Ahn practices Internal Medicine Physician in Lakewood, CA.
Where does Dr. Woo Sung Ahn practice?
Dr. Woo Sung Ahn practices at 20145 S Pioneer Blvd, Lakewood, CA 907151051. Office phone: 5629165020.
What is Dr. Woo Sung Ahn's NPI?
Dr. Woo Sung Ahn's National Provider Identifier (NPI) is 1396807806, issued by NPPES.
Does Dr. Woo Sung Ahn accept Medicare assignment?
Yes. Dr. Woo Sung Ahn accepts Medicare assignment, meaning Medicare-allowed amounts are accepted as full payment for covered services.
What procedures does Dr. Woo Sung Ahn commonly perform?
Top Medicare-reported procedures in 2023: Established patient office or other outpatient visit (HCPCS 99213); Insertion of needle into vein for collection of blood sample (HCPCS 36415); Annual wellness visit, includes a personalized prevention plan of service (pps), subsequent visit (HCPCS G0439). Source: CMS Medicare Physician & Other Practitioners file.