Doctor profile · Federal record

Dr. William Sim, MD

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

  • NPI 1437256906
  • Accepts Medicare
  • MIPS 75.0 / 100 · 2023
  • 36 yrs in practice
  • Male
  • Group practice
  • No sanctions

Practice & contact

NPPES Updated May 11, 2026
Primary practice
11480 Brookshire Ave, 200
Downey, CA 902419998
(562) 806-0874
fax (562) 927-4801

Credentials & registration

NPPES · NUCC
NPI registered
September 2006 — 20 yrs on file
Profile last updated
December 20, 2011
Year of graduation
1990 — 36 yrs since
Specialty taxonomy
207R00000X — NUCC code
State license (1)
California #G72353
Medicaid
CA #00G723520

Federal sanctions & exclusions

OIG LEIE Updated May 11, 2026

No sanctions, exclusions or revocations on file

Checked against OIG LEIE on NPI 1437256906. Last verified May 11, 2026.

Medicare procedures · 2023

Top services delivered

CMS Provider Utilization
Total services
4,892
Distinct HCPCS
10
Medicare allowed
$504,135
HCPCS Description Services Patients Avg allowed
99349 Residence visit for established patient with moderate level of medical decision making, per day, if using time, at least 40 minutes 1,541 279 $137
99213 Established patient office or other outpatient visit, 20-29 minutes 791 251 $100
99214 Established patient office or other outpatient visit, 30-39 minutes 598 309 $141
99348 Residence visit for established patient with low level of medical decision making, per day, if using time, at least 30 minutes 449 189 $82
99490 Chronic care management services, first 20 minutes of clinical staff time directed by health care professional, per calendar month 325 44 $69
J3301 Injection, triamcinolone acetonide, not otherwise specified, 10 mg 291 48 $1
96372 Injection of drug or substance under skin or into muscle 159 64 $16
G0181 Physician or allowed practitioner supervision of a patient receiving medicare-covered services provided by a participating home health agency (patient not present) requiring complex and multidisciplinary care modalities involving regular physician or allow 115 76 $114
99345 Residence visit for new patient with high level of medical decision making, per day, if using time, at least 75 minutes 108 108 $218
99212 Established patient office or other outpatient visit, 10-19 minutes 73 61 $63

In context: peer comparison

Among 15 peers in Downey Internal Medicine Physician, average services per provider: 213. This provider delivers 23× the peer median.

Open Payments

Industry payments received

CMS Open Payments
All-time total
$1,889
Transactions
76
Manufacturers
15
Payer (manufacturer) Industry Txns Amount
Lilly USA, LLC 15 $265.92
Abbvie INC. 10 $224.27
GlaxoSmithKline, LLC. 7 $159.08
Otsuka America Pharmaceutical, INC. 7 $144.02
AstraZeneca Pharmaceuticals Lp 6 $117.36
Pfizer INC. 5 $114.89
Phathom Pharmaceuticals, INC. 4 $100.66
Ardelyx, INC. 4 $98.80
Salix Pharmaceuticals, A Division of Bausch Health US, LLC 4 $91.14
Novo Nordisk INC 4 $87.43
Novartis Pharmaceuticals Corporation 3 $61.90
Amgen INC. 2 $50.68
Ironwood Pharmaceuticals, INC 2 $43.35
Boston Scientific Corporation 1 $40.28
Radius Health, INC. 2 $40.02

By nature of payment

Food and Beverage
$1,889

Medicare Part D · 2023

Top prescriptions

CMS Part D Prescriber
Total claims
12,322
Patients
2,430
Total drug cost
$543,351
Drug Type Claims Patients Total cost
Atorvastatin Calcium Generic 1,590 326 $23,852
Losartan Potassium Generic 1,335 269 $18,157
Levothyroxine Sodium Generic 1,129 236 $20,468
Amlodipine Besylate Generic 1,010 197 $8,619
Metformin Hcl Generic 991 199 $10,622
Metoprolol Succinate Generic 956 180 $21,202
Omeprazole Generic 722 165 $10,695
Pantoprazole Sodium Generic 678 137 $10,913
Doxazosin Mesylate Generic 612 116 $16,714
Gabapentin Generic 602 99 $10,528

Hospital affiliations

CMS Hospital Compare

Frequently asked questions

Auto-generated from federal data
What is Dr. William Sim's medical specialty?
Dr. William Sim practices Internal Medicine Physician in Downey, CA.
Where does Dr. William Sim practice?
Dr. William Sim practices at 11480 Brookshire Ave, Downey, CA 902419998. Office phone: 5628060874.
What is Dr. William Sim's NPI?
Dr. William Sim's National Provider Identifier (NPI) is 1437256906, issued by NPPES.
Does Dr. William Sim accept Medicare assignment?
Yes. Dr. William Sim accepts Medicare assignment, meaning Medicare-allowed amounts are accepted as full payment for covered services.
What procedures does Dr. William Sim commonly perform?
Top Medicare-reported procedures in 2023: Residence visit for established patient with moderate level of medical decision making (HCPCS 99349); Established patient office or other outpatient visit (HCPCS 99213); Established patient office or other outpatient visit (HCPCS 99214). Source: CMS Medicare Physician & Other Practitioners file.