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Leonard Zwelling, M.D.
NPI 1003900572 · Medical Oncology Physician · Houston, TX
Leonard Zwelling, M.D. is a Medical Oncology Physician provider in Houston, TX (NPI 1003900572).
Provider details
- NPI number
- 1003900572
- Entity type
- Individual
- Primary specialty
- Medical Oncology PhysicianAllopathic & Osteopathic Physicians
- Credential
- M.D.
- Sex
- Male
- Sole proprietor
- No
- License
- G7031 (TX)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Profile Score
Detailed profile(90/100 index)
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure38% of score
19 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.
Practice location
1515 Holcombe Blvd
Houston, TX 77030-4009
Phone: (713) 792-6161
Street-level locationGet directions
Mailing address
Po Box 4439
Houston, TX 77210-4439
Registry dates
- Enumerated
- 2006-10-02
- Last updated
- 2007-12-06
Frequently asked questions
- What is Leonard Zwelling's NPI number?
- Leonard Zwelling's National Provider Identifier (NPI) is 1003900572, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Leonard Zwelling's specialty?
- Leonard Zwelling is listed in the NPPES registry with a primary specialty of Medical Oncology Physician (Allopathic & Osteopathic Physicians).
- Where is Leonard Zwelling located?
- Leonard Zwelling's practice location on file with NPPES is 1515 Holcombe Blvd, Houston, TX 77030-4009.
- What is Leonard Zwelling's phone number?
- The practice phone number listed in the NPPES registry for Leonard Zwelling is (713) 792-6161.
- Is Leonard Zwelling's NPI active?
- Yes — Leonard Zwelling's NPI (1003900572) is active in the NPPES registry as of the last update on 2007-12-06.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.