Hovsep Mahdessian, MD
NPI 1659544203 · Internal Medicine Physician · Palmdale, CA
Enrolled with Medicare as Practitioner - Internal Medicine · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Hovsep Mahdessian, MD is a Internal Medicine Physician provider in Palmdale, CA (NPI 1659544203).
Provider details
- NPI number
- 1659544203
- Entity type
- Individual
- Primary specialty
- Internal Medicine PhysicianAllopathic & Osteopathic Physicians
- Credential
- MD
- Sex
- Male
- Sole proprietor
- No
- License
- O36.120147 (IL)
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
18 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
233 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 | 77 | $139 |
| Established Patient Office Or Other Outpatient Visit With Low Level OD Decision Making, If Using Time, 20 Minutes Or More99213 | 58 | $99 |
| Automated Urinalysis Test81003 | 19 | $2 |
| Blood Test, Basic Group of Blood Chemicals (calcium, Total)80048 | 18 | $8 |
| Complete Blood Cell Count (red Cells, White Blood Cell, Platelets), Automated Test and Automated Differential White Blood Cell Count85025 | 17 | $8 |
| 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 · 67 distinct drugs on file.
| Drug | Part D claims (2024) | Beneficiaries |
|---|---|---|
| Atorvastatin Calcium | 126 | 44 |
| Methylprednisolone | 104 | 102 |
| Metformin Hcl | 87 | 33 |
| Amlodipine Besylate | 80 | 32 |
| Omeprazole | 75 | 30 |
| Gabapentin | 71 | 25 |
| Lisinopril | 68 |
Transparency — industry payments
Based on CMS Open Payments, 2024; not all care is captured.
$16 across 1 record (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
- 2008-04-03
- Last updated
- 2011-11-23
Frequently asked questions
- What is Hovsep Mahdessian's NPI number?
- Hovsep Mahdessian's National Provider Identifier (NPI) is 1659544203, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Hovsep Mahdessian's specialty?
- Hovsep Mahdessian is listed in the NPPES registry with a primary specialty of Internal Medicine Physician (Allopathic & Osteopathic Physicians).
- Where is Hovsep Mahdessian located?
- Hovsep Mahdessian's practice location on file with NPPES is 327 E Palmdale Blvd, Palmdale, CA 93550-7139.
- What is Hovsep Mahdessian's phone number?
- The practice phone number listed in the NPPES registry for Hovsep Mahdessian is (661) 273-5888.
- Does Hovsep Mahdessian accept Medicare?
- Hovsep Mahdessian is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Hovsep Mahdessian's NPI active?
- Yes — Hovsep Mahdessian's NPI (1659544203) is active in the NPPES registry as of the last update on 2011-11-23.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.