Thoi Lien, M.D.
NPI 1871653816 · Family Medicine Physician · Rosemead, CA
Enrolled with Medicare as Practitioner - Family Practice · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Thoi Lien, M.D. is a Family Medicine Physician provider in Rosemead, CA (NPI 1871653816).
Provider details
- NPI number
- 1871653816
- Entity type
- Individual
- Primary specialty
- Family Medicine PhysicianAllopathic & Osteopathic Physicians
- Credential
- M.D.
- Sex
- Male
- Sole proprietor
- Yes
- License
- A75628 (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
4,393 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 Low Level OD Decision Making, If Using Time, 20 Minutes Or More99213 | 1,599 | $99 |
| Established Patient Office Or Other Outpatient Visit With Straightforward Medical Decision Making, If Using Time, 10 Minutes Or More99212 | 555 | $59 |
| Insertion of Needle Into Vein for Collection of Blood Sample36415 | 549 | $9 |
| Subsequent Hospital Care With Moderate Levelof Medical Decision Making, If Using Time, at Least 35 Minutes99232 | 528 | $81 |
| Established Patient Office Or Other Outpatient Visit With Moderate Level of Decision Making, If Using Time, 30 Minutes Or More99214 | 467 | $139 |
| Administration of Influenza Virus VaccineG0008 |
What this provider prescribes (Medicare Part D)
Top drugs by Medicare Part D claim volume, 2024 · 215 distinct drugs on file.
| Drug | Part D claims (2024) | Beneficiaries |
|---|---|---|
| Atorvastatin Calcium | 2,314 | 366 |
| Levocetirizine Dihydrochloride | 1,503 | 324 |
| Losartan Potassium | 1,373 | 221 |
| Celecoxib | 1,287 | 267 |
| Amlodipine Besylate | 1,262 | 196 |
| Metformin Hcl | 1,213 | 187 |
| Losartan/Hydrochlorothiazidebrand: Losartan-Hydrochlorothiazide |
Transparency — industry payments
Based on CMS Open Payments, 2024; not all care is captured.
$99 across 5 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
- 2006-12-11
- Last updated
- 2021-12-10
- Certified
- 2021-12-10
Frequently asked questions
- What is Thoi Lien's NPI number?
- Thoi Lien's National Provider Identifier (NPI) is 1871653816, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Thoi Lien's specialty?
- Thoi Lien is listed in the NPPES registry with a primary specialty of Family Medicine Physician (Allopathic & Osteopathic Physicians).
- Where is Thoi Lien located?
- Thoi Lien's practice location on file with NPPES is 8054 Garvey Ave Ste 201, Rosemead, CA 91770-2449.
- What is Thoi Lien's phone number?
- The practice phone number listed in the NPPES registry for Thoi Lien is (626) 280-5035.
- Does Thoi Lien accept Medicare?
- Thoi Lien is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Thoi Lien's NPI active?
- Yes — Thoi Lien's NPI (1871653816) is active in the NPPES registry as of the last update on 2021-12-10.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.