Doctor profile · Federal record

Dr. Michael O'Brien, M.D.

Family Medicine Physician · Castro Valley, CA

  • NPI 1821181215
  • 20 yrs on file
  • Male
  • Solo practice
  • Sanctions on record

Practice & contact

NPPES Updated May 11, 2026
Primary practice
20100 Lake Chabot RD
Castro Valley, CA 945465306
(510) 581-7677

Credentials & registration

NPPES · NUCC
NPI registered
September 2006 — 20 yrs on file
Profile last updated
August 21, 2007
Specialty taxonomy
207Q00000X — NUCC code
State license (1)
California #G61152

Federal sanctions & exclusions

OIG LEIE Updated May 11, 2026

1 exclusion record on file

Always verify with the official OIG LEIE.
  • 1128b4 — excluded Dec 19, 2024 / reinstated Nov 30, -0001

Medicare procedures · 2023

Top services delivered

CMS Provider Utilization
Total services
1,104
Distinct HCPCS
10
Medicare allowed
$139,749
HCPCS Description Services Patients Avg allowed
99214 Established patient office or other outpatient visit, 30-39 minutes 430 118 $143
99309 Subsequent nursing facility care with moderate level of medical decision making, per day, if using time, at least 30 minutes 186 25 $116
99213 Established patient office or other outpatient visit, 20-29 minutes 120 66 $102
99215 Established patient office or other outpatient visit, 40-54 minutes 109 83 $200
99212 Established patient office or other outpatient visit, 10-19 minutes 59 50 $65
99310 Subsequent nursing facility care with high level of medical decision making, per day, if using time, at least 45 minutes 47 24 $165
71046 X-ray of chest, 2 views 42 37 $41
93000 Routine electrocardiogram (ecg) using at least 12 leads with interpretation and report 42 40 $17
69210 Removal of impacted ear wax 15 12 $52
99306 Initial nursing facility care with high level of medical decision making, per day, if using time, at least 45 minutes 15 13 $195

In context: peer comparison

Among 8 peers in this city , average services per provider: 203. This provider delivers 5.4× the peer median.

Open Payments

Industry payments received

CMS Open Payments
All-time total
$34
Transactions
1
Manufacturers
1
Payer (manufacturer) Industry Txns Amount
Amgen Inc. 1 $34.13

By nature of payment

Food and Beverage
$34

Medicare Part D · 2023

Top prescriptions

CMS Part D Prescriber
Total claims
1,084
Patients
184
Total drug cost
$20,976
Drug Type Claims Patients Total cost
Atorvastatin Calcium Generic 150 31 $2,617
Tamsulosin Hcl Generic 95 20 $3,309
Metoprolol Succinate Generic 88 21 $2,416
Donepezil Hcl Generic 77 0 $1,412
Levothyroxine Sodium Generic 76 13 $1,138
Gabapentin Generic 73 15 $2,196
Pantoprazole Sodium Generic 64 15 $1,940
Simvastatin Generic 64 12 $504
Lisinopril Generic 61 16 $769
Sertraline Hcl Generic 61 0 $758

Frequently asked questions

Auto-generated from federal data
What is Dr. Michael O'Brien's medical specialty?
Dr. Michael O'Brien practices Family Medicine Physician in Castro Valley, CA.
Where does Dr. Michael O'Brien practice?
Dr. Michael O'Brien practices at 20100 Lake Chabot RD, Castro Valley, CA 945465306. Office phone: 5105817677.
What is Dr. Michael O'Brien's NPI?
Dr. Michael O'Brien's National Provider Identifier (NPI) is 1821181215, issued by NPPES.
What procedures does Dr. Michael O'Brien commonly perform?
Top Medicare-reported procedures in 2023: Established patient office or other outpatient visit (HCPCS 99214); Subsequent nursing facility care with moderate level of medical decision making (HCPCS 99309); Established patient office or other outpatient visit (HCPCS 99213). Source: CMS Medicare Physician & Other Practitioners file.