Tan Nguyen, MD
Tan Nguyen, MD is an Internal Medicine Physician in Sunnyvale, CA, registered under NPI 1003256843. This provider registers 2 separate taxonomy codes, which usually means they practise across more than one recognised specialty.
Getting there
Here is what surrounds this office in Sunnyvale, based on OpenStreetMap data collected Sep 14, 2026. Parking is available about 552 ft away at PAMF Parking. There is EV charging 0.39 mi from the office (Sunnyvale Supercharger) — useful if you are driving in from out of town. The nearest transit stop is 780 ft away, served by Sunnyvale-Saratoga Road & West El Camino Real. A pharmacy sits 0.49 mi from the entrance (CVS Pharmacy), which helps if you leave with a prescription. If you arrive early, there is a coffee shop 0.30 mi away.
Getting here and what is nearby
Parking 325 ft ~2 min
Grocery Sprouts Farmers Market 293 ft ~2 min
111 East El Camino Real, Sunnyvale 94087
Mo-Su 07:00-22:00
Parking 378 ft ~2 min
Transit El Camino Real & South Sunnyvale Avenue 545 ft ~3 min
Parking PAMF Parking 552 ft ~3 min
Pharmacy Walgreens 578 ft ~3 min
105 East El Camino Real, Sunnyvale 94087
Transit El Camino Real & Sunnyvale-Saratoga Road 664 ft ~3 min
Restaurant Dave's Hot Chicken 695 ft ~3 min
118 East El Camino Real, 94087
Grocery Baraka Market 696 ft ~3 min
101 East El Camino Real, Sunnyvale 94087
Restaurant Dumpling Depot 742 ft ~3 min
Transit Sunnyvale-Saratoga Road & West El Camino Real 780 ft ~3 min
Restaurant Pizza My Heart 781 ft ~3 min
110 East El Camino Real, 94087
Mo-Su 11:00-22:00
Hotel Wittle Inn 903 ft ~4 min
Coffee Peet's Coffee 926 ft ~4 min
Grocery Safeway 0.27 mi ~6 min
Coffee Heytea 0.30 mi ~6 min
Coffee Starbucks 0.30 mi ~7 min
348 West El Camino Real, Sunnyvale 94087
05:30-20:00
EV charging ChargePoint 0.38 mi ~8 min
EV charging ChargePoint 0.38 mi ~8 min
EV charging Sunnyvale Supercharger 0.39 mi ~8 min
Pharmacy CVS Pharmacy 0.40 mi ~8 min
Gas station Fair Oaks Gas 0.41 mi ~9 min
Convenience Fair Oaks Gas 0.42 mi ~9 min
603 Old San Francisco Road, Sunnyvale 94086
Convenience 7-Eleven 0.44 mi ~9 min
615 Old San Francisco Road, Sunnyvale 94086
24/7
Hotel AC Hotel Sunnyvale 0.48 mi ~10 min
Pharmacy CVS Pharmacy 0.49 mi ~10 min
Distances are straight‑line estimates — walking routes may be longer. Hours and phone numbers can change; call ahead to confirm.
Credentials and Medicare
| Licence | State | Specialty |
|---|---|---|
| A140731 | CA | Internal Medicine Physician primary |
This provider holds licence A140731 issued in CA. A licence number in NPPES reflects what was filed at registration — it does not confirm the licence is still active today.
- Status
- Approved
- Provider type
- Practitioner - Internal Medicine
- PAC ID
- 9537457064
- Enrollment ID
- I20161014001914
Medicare enrolment is recorded as approved under the provider type Practitioner - Internal Medicine. Being enrolled means the provider can bill Medicare; it does not tell you whether they are currently accepting new Medicare patients. Call the office to confirm.
What Internal Medicine covers
A physician who provides long-term, comprehensive care in the office and the hospital, managing both common and complex illness of adolescents, adults and the elderly. Internists are trained in the diagnosis and treatment of cancer, infections and diseases affecting the heart, blood, kidneys, joints and digestive, respiratory and vascular systems. They are also trained in the essentials of primary care internal medicine, which incorporates an understanding of disease prevention, wellness, substance abuse, mental health and effective treatment of common problems of the eyes, ears, skin, nervous system and reproductive organs. NUCC Health Care Provider Taxonomy, code 207R00000X
All registered taxonomy codes
This provider registers 2 taxonomy codes. The primary code is what appears on most claims; the others record additional recognised specialties.
| Code | Specialty | Licence | State | |
|---|---|---|---|---|
| 207R00000X | Internal Medicine Physician | A140731 | CA | primary |
| 390200000X | Student in an Organized Health Care Education/Training Program | — | NY |
The taxonomy records how the provider classifies their own practice. It does not confirm which conditions they currently treat, whether they are accepting new patients, or which insurance they take — call the office for that.
Full NPPES record
An NPI-1 identifies a single person. It stays with the clinician for life, even if they move practice or change state, which is why the address on file can lag behind where they actually work today.
| NPI | 1003256843 valid check digit |
|---|---|
| Entity type | Individual (NPI-1) |
| Enumeration date | Jun 25, 2013 |
| Last updated | Oct 10, 2016 |
| Status | Active |
| Sole proprietor | No |
| Gender | Male |
| Credential | MD |
| Practice address |
301 OLD SAN FRANCISCO RD Sunnyvale, CA 94086 (408) 730-4360 |
| Mailing address |
2350 W. EL CAMINO REAL 2ND FLOOR Mountain View, CA 94040 |
Number check
How the check works, step by step
Every NPI carries a Luhn check digit — the same scheme used on credit cards. CMS prefixes the number with 80840 before computing it, which marks it as a US health identifier.
| Digit | 8 | 0 | 8 | 4 | 0 | 1 | 0 | 0 | 3 | 2 | 5 | 6 | 8 | 4 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Doubled? | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 |
| Value | 8 | 0 | 8 | 8 | 0 | 2 | 0 | 0 | 3 | 4 | 5 | 3 | 8 | 8 |
Sum = 57 · next multiple of 10 = 60 · check digit = 3 · actual last digit = 3
A valid check digit only means the number is well-formed. It does not mean the provider is licensed, active, or in good standing — those are separate questions answered by the sections above.