Hassan Alissa, MD
NPI 1770522633 · Rheumatology Physician · San Marcos, TX
Enrolled with Medicare as Practitioner - Rheumatology · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Hassan Alissa, MD is a Rheumatology Physician provider in San Marcos, TX (NPI 1770522633).
Provider details
- NPI number
- 1770522633
- Entity type
- Individual
- Primary specialty
- Rheumatology PhysicianAllopathic & Osteopathic Physicians
- Credential
- MD
- Sex
- Male
- Sole proprietor
- Yes
- License
- 2000160315 (MO)
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
2,842 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) |
|---|---|---|
| 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 | 1,036 | $16 |
| Established Patient Office Or Other Outpatient Visit With Moderate Level of Decision Making, If Using Time, 30 Minutes Or More99214 | 801 | $117 |
| Established Patient Office Or Other Outpatient Visit With Low Level OD Decision Making, If Using Time, 20 Minutes Or More99213 | 704 | $86 |
| Injection of Drug Or Substance Under Skin Or Into Muscle96372 | 226 | $13 |
| New Patient Office Or Other Outpatient Visit With Moderate Level of Medical Decision Making, If Using Time, 45 Minutes Or More99204 | 39 | $156 |
What this provider prescribes (Medicare Part D)
Top drugs by Medicare Part D claim volume, 2024 · 43 distinct drugs on file.
| Drug | Part D claims (2024) | Beneficiaries |
|---|---|---|
| Hydroxychloroquine Sulfate | 381 | 169 |
| Prednisone | 320 | 149 |
| Tramadol Hcl | 126 | 26 |
| Leflunomide | 105 | 43 |
| Methotrexate Sodiumbrand: Methotrexate | 96 | 52 |
| Hydrocodone/Acetaminophenbrand: Hydrocodone-Acetaminophen | 90 | 12 |
| Meloxicam |
Transparency — industry payments
Based on CMS Open Payments, 2024; not all care is captured.
$983 across 50 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
- 2006-06-06
- Last updated
- 2014-02-14
Frequently asked questions
- What is Hassan Alissa's NPI number?
- Hassan Alissa's National Provider Identifier (NPI) is 1770522633, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Hassan Alissa's specialty?
- Hassan Alissa is listed in the NPPES registry with a primary specialty of Rheumatology Physician (Allopathic & Osteopathic Physicians).
- Where is Hassan Alissa located?
- Hassan Alissa's practice location on file with NPPES is 1340 Wonder World Dr, San Marcos, TX 78666-7598.
- What is Hassan Alissa's phone number?
- The practice phone number listed in the NPPES registry for Hassan Alissa is (512) 667-7123.
- Does Hassan Alissa accept Medicare?
- Hassan Alissa is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Hassan Alissa's NPI active?
- Yes — Hassan Alissa's NPI (1770522633) is active in the NPPES registry as of the last update on 2014-02-14.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.