Mark Hwang, MD
NPI 1366798647 · Rheumatology Physician · Houston, TX
Enrolled with Medicare as Practitioner - Rheumatology · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Mark Hwang, MD is a Rheumatology Physician provider in Houston, TX (NPI 1366798647).
Provider details
- NPI number
- 1366798647
- Entity type
- Individual
- Primary specialty
- Rheumatology PhysicianAllopathic & Osteopathic Physicians
- Credential
- MD
- Sex
- Male
- Sole proprietor
- No
- License
- R3110 (TX)
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
13 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
46 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 | 27 | $128 |
| Visit Complexity Inherent to Evaluation and Management Associated With Medical Care Services That Serve As the Continuing Focal Point for All Needed Health Care Services And/Or With Medical Care Services That Are Part of Ongoing Care Related to a Patient'SG2211 | 19 | $17 |
Typical Medicare-allowed amounts for these services range $17–$128 (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 · 9 distinct drugs on file.
| Drug | Part D claims (2024) | Beneficiaries |
|---|---|---|
| Celecoxib | 39 | — |
| Hydroxychloroquine Sulfate | 30 | — |
| Prednisone | 25 | 12 |
| Ixekizumabbrand: Taltz Autoinjector | 24 | — |
| Adalimumabbrand: Humira(cf) Pen | 19 | — |
| Etanerceptbrand: Enbrel | 17 | — |
| Gabapentin |
Transparency — industry payments
Based on CMS Open Payments, 2024; not all care is captured.
$188 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
- 2012-07-24
- Last updated
- 2018-10-29
Frequently asked questions
- What is Mark Hwang's NPI number?
- Mark Hwang's National Provider Identifier (NPI) is 1366798647, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Mark Hwang's specialty?
- Mark Hwang is listed in the NPPES registry with a primary specialty of Rheumatology Physician (Allopathic & Osteopathic Physicians).
- Where is Mark Hwang located?
- Mark Hwang's practice location on file with NPPES is 6410 Fannin St Ste 450, Houston, TX 77030-3008.
- What is Mark Hwang's phone number?
- The practice phone number listed in the NPPES registry for Mark Hwang is (713) 500-6536.
- Does Mark Hwang accept Medicare?
- Mark Hwang is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Mark Hwang's NPI active?
- Yes — Mark Hwang's NPI (1366798647) is active in the NPPES registry as of the last update on 2018-10-29.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.