Mark Horowitz, MD
NPI 1154490530 · Internal Medicine Physician · New York, NY
Enrolled with Medicare as Practitioner - Internal Medicine · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Mark Horowitz, MD is a Internal Medicine Physician provider in New York, NY (NPI 1154490530).
Provider details
- NPI number
- 1154490530
- Entity type
- Individual
- Primary specialty
- Internal Medicine PhysicianAllopathic & Osteopathic Physicians
- Credential
- MD
- Sex
- Male
- Sole proprietor
- No
- License
- 1613581 (NY)
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
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
4,450 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 | 2,050 | $133 |
| Established Patient Office Or Other Outpatient Visit With High Level of Medical Decision Making, If Using Time, 40 Minutes Or More99215 | 824 | $187 |
| Insertion of Needle Into Vein for Collection of Blood Sample36415 | 645 | $9 |
| Test to Measure Expiratory Airflow and Volume Changes Before and After Medication Administration94060 | 238 | $41 |
| Ultrasound Study of Arm and Leg Arteries93922 | 210 | $87 |
| Routine Electrocardiogram (ecg) Using at Least 12 Leads With Interpretation and Report93000 |
What this provider prescribes (Medicare Part D)
Top drugs by Medicare Part D claim volume, 2024 · 70 distinct drugs on file.
| Drug | Part D claims (2024) | Beneficiaries |
|---|---|---|
| Levothyroxine Sodium | 226 | 59 |
| Atorvastatin Calcium | 202 | 58 |
| Rosuvastatin Calcium | 108 | 36 |
| Azithromycin | 94 | 59 |
| Prednisone | 92 | 27 |
| Amlodipine Besylate | 80 | 23 |
| Metformin Hcl | 78 |
Transparency — industry payments
Based on CMS Open Payments, 2024; not all care is captured.
$1,456 across 47 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
- 2006-11-07
- Last updated
- 2025-09-11
Frequently asked questions
- What is Mark Horowitz's NPI number?
- Mark Horowitz's National Provider Identifier (NPI) is 1154490530, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Mark Horowitz's specialty?
- Mark Horowitz is listed in the NPPES registry with a primary specialty of Internal Medicine Physician (Allopathic & Osteopathic Physicians).
- Where is Mark Horowitz located?
- Mark Horowitz's practice location on file with NPPES is 21 East 90th St, New York, NY 10128.
- What is Mark Horowitz's phone number?
- The practice phone number listed in the NPPES registry for Mark Horowitz is (212) 860-3077.
- Does Mark Horowitz accept Medicare?
- Mark Horowitz is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Mark Horowitz's NPI active?
- Yes — Mark Horowitz's NPI (1154490530) is active in the NPPES registry as of the last update on 2025-09-11.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.