Alex Leung, M.D
NPI 1669414512 · Internal Medicine Physician · Fullerton, CA
Enrolled with Medicare as Practitioner - Internal Medicine · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Alex Leung, M.D is a Internal Medicine Physician provider in Fullerton, CA (NPI 1669414512).
Provider details
- NPI number
- 1669414512
- Entity type
- Individual
- Primary specialty
- Internal Medicine PhysicianAllopathic & Osteopathic Physicians
- Credential
- M.D
- Sex
- Male
- Sole proprietor
- Yes
- License
- A88871 (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 tenure25% of score
20 yrs in NPPES registry
- Profile completeness25% of score
100% of core fields populated
- Practice footprint15% of score
1 documented practice location
- Medicare service volume (vs. specialty peers)25% of score
493 Medicare services, 2024 (ranked within specialty)
- Open Payments transparency10% of score
Has Open Payments disclosures (2024)
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 .
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 | 291 | $81 |
| Hospital Discharge Day Management, More Than 30 Minutes99239 | 91 | $119 |
| Subsequent Hospital Care With Moderate Levelof Medical Decision Making, If Using Time, at Least 50 Minutes99233 | 36 | $122 |
| Initial Hospital Care With Straightforward Or Low-Level Medical Decision Making, If Using Time, at Least 55 Minutes99222 | 34 | $132 |
| Initial Hospital Care With Moderate Level of Medical Decision Making, If Using Time, at Least 75 Minutes99223 | 30 | $179 |
| Initial Hospital Care With Same-Day Admission and Discharge With Moderate Level of Medical Decision Making, Per Day, If Using Time, at Least 70 Minutes |
What this provider prescribes (Medicare Part D)
Top drugs by Medicare Part D claim volume, 2024 · 13 distinct drugs on file.
| Drug | Part D claims (2024) | Beneficiaries |
|---|---|---|
| Cefpodoxime Proxetil | 35 | 35 |
| Potassium Chloride | 33 | 19 |
| Furosemide | 32 | 18 |
| Pantoprazole Sodium | 19 | 12 |
| Apixabanbrand: Eliquis | 17 | — |
| Azithromycin | 16 | 16 |
| Methylprednisolone | 15 | 15 |
Transparency — industry payments
Based on CMS Open Payments, 2024; not all care is captured.
$352 across 11 records (Open Payments 2024)
Open Payments discloses payments and transfers of value (meals, travel, consulting, research, royalties) from drug and device makers to providers. This is a transparency signal, not a verdict — such payments are legal and common, and their presence is neither an endorsement nor a criticism. Source: CMS Open Payments, program year 2024.
Practice location
Mailing address
Registry dates
- Enumerated
- 2006-06-12
- Last updated
- 2009-11-23
Frequently asked questions
- What is Alex Leung's NPI number?
- Alex Leung's National Provider Identifier (NPI) is 1669414512, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Alex Leung's specialty?
- Alex Leung is listed in the NPPES registry with a primary specialty of Internal Medicine Physician (Allopathic & Osteopathic Physicians).
- Where is Alex Leung located?
- Alex Leung's practice location on file with NPPES is 279 Imperial Hwy, Fullerton, CA 92835-1041.
- What is Alex Leung's phone number?
- The practice phone number listed in the NPPES registry for Alex Leung is (714) 449-4842.
- Does Alex Leung accept Medicare?
- Alex Leung is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Alex Leung's NPI active?
- Yes — Alex Leung's NPI (1669414512) is active in the NPPES registry as of the last update on 2009-11-23.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.