Tatiana Tam, DO
NPI 1790304988 · Internal Medicine Physician · Vallejo, CA
Enrolled with Medicare as Practitioner - Internal Medicine · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Tatiana Tam, DO is a Internal Medicine Physician provider in Vallejo, CA (NPI 1790304988).
Provider details
- NPI number
- 1790304988
- Entity type
- Individual
- Primary specialty
- Internal Medicine PhysicianAllopathic & Osteopathic Physicians
- Credential
- DO
- Sex
- Female
- Sole proprietor
- No
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Student, Health Care
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure28% of score
6 yrs in NPPES registry
- Profile completeness28% of score
83% of core fields populated
- Practice footprint17% of score
1 documented practice location
- Medicare service volume (vs. specialty peers)28% of score
108 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) |
|---|---|---|
| Subsequent Hospital Care With Moderate Levelof Medical Decision Making, If Using Time, at Least 35 Minutes99232 | 91 | $84 |
| Hospital Discharge Day Management, 30 Minutes Or Less99238 | 17 | $87 |
Typical Medicare-allowed amounts for these services range $84–$87 (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 · 10 distinct drugs on file.
| Drug | Part D claims (2024) | Beneficiaries |
|---|---|---|
| Furosemide | 33 | 20 |
| Atorvastatin Calcium | 21 | 16 |
| Doxycycline Monohydrate | 21 | 21 |
| Amoxicillin/Potassium Clavbrand: Amoxicillin-Clavulanate Potass | 20 | 20 |
| Amlodipine Besylate | 18 | 17 |
| Metoprolol Succinate | 18 | 14 |
| Prednisone | 15 |
Practice location
Mailing address
Registry dates
- Enumerated
- 2020-04-08
- Last updated
- 2023-08-31
- Certified
- 2023-08-31
Frequently asked questions
- What is Tatiana Tam's NPI number?
- Tatiana Tam's National Provider Identifier (NPI) is 1790304988, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Tatiana Tam's specialty?
- Tatiana Tam is listed in the NPPES registry with a primary specialty of Internal Medicine Physician (Allopathic & Osteopathic Physicians).
- Where is Tatiana Tam located?
- Tatiana Tam's practice location on file with NPPES is 975 Sereno Dr, Vallejo, CA 94589-2441.
- What is Tatiana Tam's phone number?
- The practice phone number listed in the NPPES registry for Tatiana Tam is (707) 651-1000.
- Does Tatiana Tam accept Medicare?
- Tatiana Tam is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Tatiana Tam's NPI active?
- Yes — Tatiana Tam's NPI (1790304988) is active in the NPPES registry as of the last update on 2023-08-31.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.