Marcus Lum, MD
NPI 1003839242 · Family Medicine Physician · La Mirada, CA
Enrolled with Medicare as Practitioner - Family Practice · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Marcus Lum, MD is a Family Medicine Physician provider in La Mirada, CA (NPI 1003839242).
Provider details
- NPI number
- 1003839242
- Entity type
- Individual
- Primary specialty
- Family Medicine PhysicianAllopathic & Osteopathic Physicians
- Credential
- MD
- Sex
- Male
- Sole proprietor
- No
- License
- G073347 (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
320 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 | 155 | $99 |
| Established Patient Office Or Other Outpatient Visit With Moderate Level of Decision Making, If Using Time, 30 Minutes Or More99214 | 68 | $138 |
| Annual Wellness Visit, Includes a Personalized Prevention Plan of Service (pps), Subsequent VisitG0439 | 46 | $140 |
| Insertion of Needle Into Vein for Collection of Blood Sample36415 | 24 | $9 |
| Urinalysis, Manual Test81002 | 14 | $3 |
| Administration of Influenza Virus VaccineG0008 | 13 | $34 |
What this provider prescribes (Medicare Part D)
Top drugs by Medicare Part D claim volume, 2024 · 123 distinct drugs on file.
| Drug | Part D claims (2024) | Beneficiaries |
|---|---|---|
| Atorvastatin Calcium | 780 | 220 |
| Amlodipine Besylate | 314 | 96 |
| Levothyroxine Sodium | 287 | 70 |
| Lisinopril | 284 | 84 |
| Rosuvastatin Calcium | 279 | 80 |
| Losartan Potassium | 251 | 77 |
| Tamsulosin Hcl |
Transparency — industry payments
Based on CMS Open Payments, 2024; not all care is captured.
$1,012 across 48 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
- 2006-07-26
- Last updated
- 2007-07-08
Frequently asked questions
- What is Marcus Lum's NPI number?
- Marcus Lum's National Provider Identifier (NPI) is 1003839242, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Marcus Lum's specialty?
- Marcus Lum is listed in the NPPES registry with a primary specialty of Family Medicine Physician (Allopathic & Osteopathic Physicians).
- Where is Marcus Lum located?
- Marcus Lum's practice location on file with NPPES is 15034 Imperial Hwy, La Mirada, CA 90638-1301.
- What is Marcus Lum's phone number?
- The practice phone number listed in the NPPES registry for Marcus Lum is (562) 902-3000.
- Does Marcus Lum accept Medicare?
- Marcus Lum is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Marcus Lum's NPI active?
- Yes — Marcus Lum's NPI (1003839242) is active in the NPPES registry as of the last update on 2007-07-08.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.