Mark Weissig, M.D.
NPI 1649266032 · Pulmonary Disease Physician · Fullerton, CA
Enrolled with Medicare as Practitioner - Pulmonary Disease · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Mark Weissig, M.D. is a Pulmonary Disease Physician provider in Fullerton, CA (NPI 1649266032).
Provider details
- NPI number
- 1649266032
- Entity type
- Individual
- Primary specialty
- Pulmonary Disease PhysicianAllopathic & Osteopathic Physicians
- Credential
- M.D.
- Sex
- Male
- Sole proprietor
- No
- License
- G49175 (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
1,555 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 | 775 | $98 |
| Established Patient Office Or Other Outpatient Visit With Moderate Level of Decision Making, If Using Time, 30 Minutes Or More99214 | 352 | $138 |
| Test to Measure Expiratory Airflow and Volume Changes Before and After Medication Administration94060 | 136 | $44 |
| Test to Examine How Well the Lungs Exchange Gases94729 | 102 | $65 |
| Test to Determine Lung Volumes Using Sensors94726 | 101 | $64 |
| New Patient Office Or Other Outpatient Visit With a High Level of Medical Decision Making, If Using Time, 60 Minutes Or More99205 |
What this provider prescribes (Medicare Part D)
Top drugs by Medicare Part D claim volume, 2024 · 79 distinct drugs on file.
| Drug | Part D claims (2024) | Beneficiaries |
|---|---|---|
| Fluticasone/Umeclidin/Vilanterbrand: Trelegy Ellipta | 439 | 112 |
| Albuterol Sulfatebrand: Albuterol Sulfate Hfa | 310 | 140 |
| Prednisone | 299 | 104 |
| Budesonide/Glycopyr/Formoterolbrand: Breztri Aerosphere | 268 | 76 |
| Montelukast Sodium | 262 | 73 |
| Furosemide | 237 | 78 |
Transparency — industry payments
Based on CMS Open Payments, 2024; not all care is captured.
$346 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
- 2005-09-21
- Last updated
- 2013-04-25
Frequently asked questions
- What is Mark Weissig's NPI number?
- Mark Weissig's National Provider Identifier (NPI) is 1649266032, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Mark Weissig's specialty?
- Mark Weissig is listed in the NPPES registry with a primary specialty of Pulmonary Disease Physician (Allopathic & Osteopathic Physicians).
- Where is Mark Weissig located?
- Mark Weissig's practice location on file with NPPES is 2141 N Harbor Blvd, Fullerton, CA 92835-3827.
- What is Mark Weissig's phone number?
- The practice phone number listed in the NPPES registry for Mark Weissig is (714) 626-8610.
- Does Mark Weissig accept Medicare?
- Mark Weissig is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Mark Weissig's NPI active?
- Yes — Mark Weissig's NPI (1649266032) is active in the NPPES registry as of the last update on 2013-04-25.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.