Doctor profile · Federal record

Dr. Tammy Chen, MD

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

  • NPI 1093887721
  • Accepts Medicare
  • 44 yrs in practice
  • Female
  • Group practice
  • No sanctions

Practice & contact

NPPES Updated May 11, 2026
Primary practice
818 Webster St
Oakland, CA 946074220
(510) 986-6830
fax (510) 986-6890

Credentials & registration

NPPES · NUCC
NPI registered
November 2006 — 20 yrs on file
Profile last updated
July 8, 2007
Year of graduation
1982 — 44 yrs since
Specialty taxonomy
207Q00000X — NUCC code
State license (1)
California #A90848

Federal sanctions & exclusions

OIG LEIE Updated May 11, 2026

No sanctions, exclusions or revocations on file

Checked against OIG LEIE on NPI 1093887721. Last verified May 11, 2026.

Medicare procedures · 2023

Top services delivered

CMS Provider Utilization
Total services
70
Distinct HCPCS
1
Medicare allowed
$1,227
HCPCS Description Services Patients Avg allowed
93000 Routine electrocardiogram (ecg) using at least 12 leads with interpretation and report 70 68 $18

In context: peer comparison

Among 24 peers in this city , average services per provider: 77. This provider delivers 0.9× the peer median.

Medicare Part D · 2023

Top prescriptions

CMS Part D Prescriber
Total claims
1,260
Patients
693
Total drug cost
$37,911
Drug Type Claims Patients Total cost
Atorvastatin Calcium Generic 142 68 $5,104
Diclofenac Sodium Generic 128 86 $6,543
Amlodipine Besylate Generic 127 59 $3,612
Losartan Potassium Generic 125 57 $4,448
Baclofen Generic 114 75 $1,429
Famotidine Generic 104 61 $2,323
Lisinopril Generic 69 33 $1,353
Gabapentin Generic 68 36 $2,180
Metoprolol Succinate Generic 64 29 $1,746
Fluticasone Propionate Generic 60 41 $1,063

Hospital affiliations

CMS Hospital Compare

Frequently asked questions

Auto-generated from federal data
What is Dr. Tammy Chen's medical specialty?
Dr. Tammy Chen practices Family Medicine Physician in Oakland, CA.
Where does Dr. Tammy Chen practice?
Dr. Tammy Chen practices at 818 Webster St, Oakland, CA 946074220. Office phone: 5109866830.
What is Dr. Tammy Chen's NPI?
Dr. Tammy Chen's National Provider Identifier (NPI) is 1093887721, issued by NPPES.
Does Dr. Tammy Chen accept Medicare assignment?
Yes. Dr. Tammy Chen accepts Medicare assignment, meaning Medicare-allowed amounts are accepted as full payment for covered services.
What procedures does Dr. Tammy Chen commonly perform?
Top Medicare-reported procedures in 2023: Routine electrocardiogram (ecg) using at least 12 leads with interpretation and report (HCPCS 93000). Source: CMS Medicare Physician & Other Practitioners file.