Alex Quan, MD
NPI 1659442630 · Internal Medicine Physician · Fontana, CA
Enrolled with Medicare as Practitioner - Internal Medicine · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Alex Quan, MD is a Internal Medicine Physician provider in Fontana, CA (NPI 1659442630).
Provider details
- NPI number
- 1659442630
- Entity type
- Individual
- Primary specialty
- Internal Medicine PhysicianAllopathic & Osteopathic Physicians
- Credential
- MD
- Sex
- Male
- Sole proprietor
- No
- License
- A73794 (CA)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure38% of score
19 yrs in NPPES registry
- Profile completeness38% of score
100% of core fields populated
- Practice footprint23% of score
1 documented practice location
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 prescribes (Medicare Part D)
Top drugs by Medicare Part D claim volume, 2024 · 80 distinct drugs on file.
| Drug | Part D claims (2024) | Beneficiaries |
|---|---|---|
| Atorvastatin Calcium | 428 | 142 |
| Amlodipine Besylate | 253 | 90 |
| Lisinopril | 163 | 57 |
| Losartan Potassium | 151 | 53 |
| Levothyroxine Sodium | 136 | 36 |
| Metformin Hcl | 129 | 49 |
| Omeprazole |
Practice location
Mailing address
Registry dates
- Enumerated
- 2006-11-13
- Last updated
- 2021-11-29
Frequently asked questions
- What is Alex Quan's NPI number?
- Alex Quan's National Provider Identifier (NPI) is 1659442630, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Alex Quan's specialty?
- Alex Quan is listed in the NPPES registry with a primary specialty of Internal Medicine Physician (Allopathic & Osteopathic Physicians).
- Where is Alex Quan located?
- Alex Quan's practice location on file with NPPES is 9961 Sierra Ave, Fontana, CA 92335-6720.
- What is Alex Quan's phone number?
- The practice phone number listed in the NPPES registry for Alex Quan is (909) 427-3910.
- Does Alex Quan accept Medicare?
- Alex Quan is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Alex Quan's NPI active?
- Yes — Alex Quan's NPI (1659442630) is active in the NPPES registry as of the last update on 2021-11-29.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.