Warren Woo, M.D.
NPI 1447340336 · Family Medicine Physician · Placentia, CA
Enrolled with Medicare as Practitioner - Family Practice · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Warren Woo, M.D. is a Family Medicine Physician provider in Placentia, CA (NPI 1447340336).
Provider details
- NPI number
- 1447340336
- Entity type
- Individual
- Primary specialty
- Family Medicine PhysicianAllopathic & Osteopathic Physicians
- Credential
- M.D.
- Sex
- Male
- Sole proprietor
- Yes
- License
- C40927 (CA)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure25% of score
19 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
441 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) |
|---|---|---|
| Established Patient Office Or Other Outpatient Visit With Moderate Level of Decision Making, If Using Time, 30 Minutes Or More99214 | 284 | $138 |
| Established Patient Office Or Other Outpatient Visit With Low Level OD Decision Making, If Using Time, 20 Minutes Or More99213 | 119 | $97 |
| Insertion of Needle Into Vein for Collection of Blood Sample36415 | 20 | $9 |
| Administration of Influenza Virus VaccineG0008 | 18 | $35 |
Typical Medicare-allowed amounts for these services range $9–$138 (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 · 41 distinct drugs on file.
| Drug | Part D claims (2024) | Beneficiaries |
|---|---|---|
| Atorvastatin Calcium | 101 | 37 |
| Rosuvastatin Calcium | 96 | 31 |
| Losartan Potassium | 80 | 27 |
| Levothyroxine Sodium | 56 | 22 |
| Metoprolol Succinate | 56 | 16 |
| Amlodipine Besylate | 50 | 24 |
| Gabapentin |
Transparency — industry payments
Based on CMS Open Payments, 2024; not all care is captured.
$153 across 2 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
- 2006-10-13
- Last updated
- 2011-09-30
Frequently asked questions
- What is Warren Woo's NPI number?
- Warren Woo's National Provider Identifier (NPI) is 1447340336, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Warren Woo's specialty?
- Warren Woo is listed in the NPPES registry with a primary specialty of Family Medicine Physician (Allopathic & Osteopathic Physicians).
- Where is Warren Woo located?
- Warren Woo's practice location on file with NPPES is 1275 N Rose Dr, Placentia, CA 92870-3941.
- What is Warren Woo's phone number?
- The practice phone number listed in the NPPES registry for Warren Woo is (714) 961-1635.
- Does Warren Woo accept Medicare?
- Warren Woo is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Warren Woo's NPI active?
- Yes — Warren Woo's NPI (1447340336) is active in the NPPES registry as of the last update on 2011-09-30.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.