Theresa Tseng, M.D.
NPI 1558466979 · Family Medicine Physician · Alhambra, CA
Enrolled with Medicare as Practitioner - Internal Medicine · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Theresa Tseng, M.D. is a Family Medicine Physician provider in Alhambra, CA (NPI 1558466979).
Provider details
- NPI number
- 1558466979
- Entity type
- Individual
- Primary specialty
- Family Medicine PhysicianAllopathic & Osteopathic Physicians
- Credential
- M.D.
- Sex
- Female
- Sole proprietor
- Yes
- License
- A383980 (CA)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Allopathic & Osteopathic Physicians
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure28% of score
19 yrs in NPPES registry
- Profile completeness28% of score
100% of core fields populated
- Practice footprint17% of score
1 documented practice location
- Medicare service volume (vs. specialty peers)28% of score
263 Medicare services, 2024 (ranked within specialty)
Medicare volume is ranked against active providers in the same specialty. Signals a provider has no public data for (e.g. Medicare claims) are left out of the score entirely — never counted as zero — so providers without that data are not penalized. See the full formula and weights in our methodology.
What this provider does (Medicare)
Based on Medicare fee-for-service claims, 2024; not all care is captured.
| Service (HCPCS) | Medicare services | Typical Medicare-allowed (2024) |
|---|---|---|
| Established Patient Office Or Other Outpatient Visit With Low Level OD Decision Making, If Using Time, 20 Minutes Or More99213 | 173 | $94 |
| Annual Wellness Visit, Includes a Personalized Prevention Plan of Service (pps), Subsequent VisitG0439 | 50 | $133 |
| Annual Depression Screening, 5 to 15 MinutesG0444 | 40 | $20 |
Typical Medicare-allowed amounts for these services range $20–$133 (2024). The Medicare-allowed amount is what Medicare recognizes for a service under fee-for-service — a reference figure for 2024, not a price quote and not what you would be billed. Medicare Part B covers roughly an eighth of all NPIs (65+ skew); services with fewer than 11 beneficiaries are suppressed by CMS. Source: CMS Medicare Physician & Other Practitioners, by Provider & Service.
What this provider prescribes (Medicare Part D)
Top drugs by Medicare Part D claim volume, 2024 · 25 distinct drugs on file.
| Drug | Part D claims (2024) | Beneficiaries |
|---|---|---|
| Atorvastatin Calcium | 270 | 73 |
| Losartan Potassium | 186 | 54 |
| Amlodipine Besylate | 140 | 40 |
| Metformin Hcl | 87 | 21 |
| Losartan/Hydrochlorothiazidebrand: Losartan-Hydrochlorothiazide | 70 | 20 |
| Simvastatin | 60 | 16 |
| Alendronate Sodium | 50 |
Practice location
Mailing address
Registry dates
- Enumerated
- 2006-09-13
- Last updated
- 2011-06-28
Frequently asked questions
- What is Theresa Tseng's NPI number?
- Theresa Tseng's National Provider Identifier (NPI) is 1558466979, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Theresa Tseng's specialty?
- Theresa Tseng is listed in the NPPES registry with a primary specialty of Family Medicine Physician (Allopathic & Osteopathic Physicians).
- Where is Theresa Tseng located?
- Theresa Tseng's practice location on file with NPPES is 1153 S Garfield Ave, Alhambra, CA 91801-4714.
- What is Theresa Tseng's phone number?
- The practice phone number listed in the NPPES registry for Theresa Tseng is (626) 281-1961.
- Does Theresa Tseng accept Medicare?
- Theresa Tseng is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Theresa Tseng's NPI active?
- Yes — Theresa Tseng's NPI (1558466979) is active in the NPPES registry as of the last update on 2011-06-28.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.