Marcela Horvitz-Lennon, MD
NPI 1528189073 · Psychiatry Physician · Somerville, MA
Enrolled with Medicare as Practitioner - Psychiatry · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Marcela Horvitz-Lennon, MD is a Psychiatry Physician provider in Somerville, MA (NPI 1528189073).
Provider details
- NPI number
- 1528189073
- Entity type
- Individual
- Primary specialty
- Psychiatry PhysicianAllopathic & Osteopathic Physicians
- Credential
- MD
- Sex
- Female
- Sole proprietor
- No
- License
- MD425424 (PA)
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 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.
What this provider prescribes (Medicare Part D)
Top drugs by Medicare Part D claim volume, 2024 · 24 distinct drugs on file.
| Drug | Part D claims (2024) |
|---|---|
| Clozapine | 124 |
| Sertraline Hcl | 89 |
| Lorazepam | 53 |
| Olanzapine | 50 |
| Haloperidol | 39 |
| Benztropine Mesylate | 34 |
| Perphenazine | 33 |
| Quetiapine Fumarate | 28 |
| Aripiprazole | 25 |
| Clonazepam | 24 |
These counts cover prescriptions paid through Medicare Part D in 2024 — they include cash-pay, commercial-insurance, Medicaid, or Part B–administered drugs, and badly undercount high cash-pay categories (e.g. GLP-1 weight-loss, testosterone, and ED medications). Any drug with 10 or fewer claims is omitted by CMS, and beneficiary counts under 11 are suppressed — so a missing drug means , never zero. This is a factual claims summary, not an endorsement, not medical advice, and not a consumer report. Source: CMS Medicare Part D Prescribers — by Provider and Drug.
Practice location
Mailing address
Registry dates
- Enumerated
- 2007-04-03
- Last updated
- 2016-08-20
Frequently asked questions
- What is Marcela Horvitz-Lennon's NPI number?
- Marcela Horvitz-Lennon's National Provider Identifier (NPI) is 1528189073, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Marcela Horvitz-Lennon's specialty?
- Marcela Horvitz-Lennon is listed in the NPPES registry with a primary specialty of Psychiatry Physician (Allopathic & Osteopathic Physicians).
- Where is Marcela Horvitz-Lennon located?
- Marcela Horvitz-Lennon's practice location on file with NPPES is 26 Central Street, Somerville, MA 02145.
- What is Marcela Horvitz-Lennon's phone number?
- The practice phone number listed in the NPPES registry for Marcela Horvitz-Lennon is (617) 591-6300.
- Does Marcela Horvitz-Lennon accept Medicare?
- Marcela Horvitz-Lennon is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Marcela Horvitz-Lennon's NPI active?
- Yes — Marcela Horvitz-Lennon's NPI (1528189073) is active in the NPPES registry as of the last update on 2016-08-20.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.