Doctor profile · Federal record

Dr. Maciej Ossowski, M. D.

Family Medicine Physician (CMS: Family Practice) · Merced, CA

  • NPI 1346207883
  • 53 yrs in practice
  • Male
  • Solo practice
  • No sanctions

Practice & contact

NPPES Updated May 11, 2026
Primary practice
3349 G St Ste D, Suite D
Merced, CA 953400978
(209) 722-8040
fax (209) 722-0287

Credentials & registration

NPPES · NUCC
NPI registered
April 2006 — 20 yrs on file
Profile last updated
July 19, 2012
Year of graduation
1973 — 53 yrs since
Specialty taxonomy
207Q00000X — NUCC code
State license (1)
California #00A383800

Federal sanctions & exclusions

OIG LEIE Updated May 11, 2026

No sanctions, exclusions or revocations on file

Checked against OIG LEIE on NPI 1346207883. Last verified May 11, 2026.

Medicare procedures · 2023

Top services delivered

CMS Provider Utilization
Total services
1,697
Distinct HCPCS
9
Medicare allowed
$156,577
HCPCS Description Services Patients Avg allowed
99214 Established patient office or other outpatient visit, 30-39 minutes 665 148 $123
99213 Established patient office or other outpatient visit, 20-29 minutes 662 162 $87
G0439 Annual wellness visit, includes a personalized prevention plan of service (pps), subsequent visit 91 91 $125
83036 Hemoglobin a1c level 73 41 $10
G0442 Annual alcohol misuse screening, 5 to 15 minutes 71 71 $18
G0444 Annual depression screening, 5 to 15 minutes 69 69 $18
96372 Injection of drug or substance under skin or into muscle 30 13 $14
81002 Urinalysis, manual test 24 22 $3
G0402 Initial preventive physical examination; face-to-face visit, services limited to new beneficiary during the first 12 months of medicare enrollment 12 12 $160

In context: peer comparison

Among 22 peers in Merced Family Medicine Physician, average services per provider: 116. This provider delivers 15× the peer median.

Open Payments

Industry payments received

CMS Open Payments
All-time total
$89
Transactions
4
Manufacturers
4
Payer (manufacturer) Industry Txns Amount
Bayer Healthcare Pharmaceuticals INC. 1 $25.97
Baxter Healthcare 1 $25.51
Novo Nordisk INC 1 $21.26
Lilly USA, LLC 1 $16.69

By nature of payment

Food and Beverage
$89

Medicare Part D · 2023

Top prescriptions

CMS Part D Prescriber
Total claims
1,237
Patients
334
Total drug cost
$83,415
Drug Type Claims Patients Total cost
Hydrocodone-Acetaminophen (Hydrocodone/Acetaminophen) Brand 180 27 $5,363
Atorvastatin Calcium Generic 179 58 $3,147
Alprazolam Generic 104 19 $972
Montelukast Sodium Generic 82 24 $1,528
Albuterol Sulfate Hfa (Albuterol Sulfate) Brand 78 32 $2,767
Amlodipine Besylate Generic 74 20 $664
Ezetimibe Generic 72 19 $3,448
Levothyroxine Sodium Generic 71 17 $1,448
Metoprolol Succinate Generic 66 19 $1,912
Metformin Hcl Generic 65 24 $563

Frequently asked questions

Auto-generated from federal data
What is Dr. Maciej Ossowski's medical specialty?
Dr. Maciej Ossowski practices Family Medicine Physician in Merced, CA.
Where does Dr. Maciej Ossowski practice?
Dr. Maciej Ossowski practices at 3349 G St Ste D, Merced, CA 953400978. Office phone: 2097228040.
What is Dr. Maciej Ossowski's NPI?
Dr. Maciej Ossowski's National Provider Identifier (NPI) is 1346207883, issued by NPPES.
Does Dr. Maciej Ossowski accept Medicare assignment?
Dr. Maciej Ossowski does not accept Medicare assignment for all services. Patients may be billed amounts beyond Medicare-allowed charges.
What procedures does Dr. Maciej Ossowski commonly perform?
Top Medicare-reported procedures in 2023: Established patient office or other outpatient visit (HCPCS 99214); Established patient office or other outpatient visit (HCPCS 99213); Annual wellness visit, includes a personalized prevention plan of service (pps), subsequent visit (HCPCS G0439). Source: CMS Medicare Physician & Other Practitioners file.