Kasey Siu, DO
NPI 1447811559 · Internal Medicine Physician · Downey, CA
Enrolled with Medicare as Practitioner - Internal Medicine · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Kasey Siu, DO is a Internal Medicine Physician provider in Downey, CA (NPI 1447811559).
Provider details
- NPI number
- 1447811559
- Entity type
- Individual
- Primary specialty
- Internal Medicine PhysicianAllopathic & Osteopathic Physicians
- Credential
- DO
- Sex
- Female
- Sole proprietor
- Yes
- License
- 20A20152 (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
6 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 · 39 distinct drugs on file.
| Drug | Part D claims (2024) | Beneficiaries |
|---|---|---|
| Atorvastatin Calcium | 161 | 70 |
| Amlodipine Besylate | 128 | 51 |
| Losartan Potassium | 107 | 39 |
| Lisinopril | 101 | 38 |
| Rosuvastatin Calcium | 82 | 32 |
| Pantoprazole Sodium | 51 | 21 |
| Tamsulosin Hcl |
Practice location
Mailing address
Registry dates
- Enumerated
- 2019-06-28
- Last updated
- 2025-10-10
- Certified
- 2025-10-10
Frequently asked questions
- What is Kasey Siu's NPI number?
- Kasey Siu's National Provider Identifier (NPI) is 1447811559, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Kasey Siu's specialty?
- Kasey Siu is listed in the NPPES registry with a primary specialty of Internal Medicine Physician (Allopathic & Osteopathic Physicians).
- Where is Kasey Siu located?
- Kasey Siu's practice location on file with NPPES is 11500 Brookshire Ave, Downey, CA 90241-4917.
- What is Kasey Siu's phone number?
- The practice phone number listed in the NPPES registry for Kasey Siu is (562) 904-5000.
- Does Kasey Siu accept Medicare?
- Kasey Siu is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Kasey Siu's NPI active?
- Yes — Kasey Siu's NPI (1447811559) is active in the NPPES registry as of the last update on 2025-10-10.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.