Mark Hreish
NPI 1164839502 · Psychiatry Physician · Riverside, CA
Enrolled with Medicare as Practitioner - Psychiatry · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Mark Hreish is a Psychiatry Physician provider in Riverside, CA (NPI 1164839502).
Provider details
- NPI number
- 1164839502
- Entity type
- Individual
- Primary specialty
- Psychiatry PhysicianAllopathic & Osteopathic Physicians
- Sex
- Male
- Sole proprietor
- No
- License
- A137381 (CA)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure38% of score
11 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 · 25 distinct drugs on file.
| Drug | Part D claims (2024) | Beneficiaries |
|---|---|---|
| Buspirone Hcl | 213 | 60 |
| Trazodone Hcl | 162 | 48 |
| Sertraline Hcl | 107 | 41 |
| Quetiapine Fumarate | 97 | 28 |
| Fluoxetine Hcl | 80 | 18 |
| Bupropion Hclbrand: Bupropion Xl | 60 | 27 |
| Escitalopram Oxalate |
Practice location
Mailing address
Registry dates
- Enumerated
- 2014-07-17
- Last updated
- 2021-12-01
Frequently asked questions
- What is Mark Hreish's NPI number?
- Mark Hreish's National Provider Identifier (NPI) is 1164839502, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Mark Hreish's specialty?
- Mark Hreish is listed in the NPPES registry with a primary specialty of Psychiatry Physician (Allopathic & Osteopathic Physicians).
- Where is Mark Hreish located?
- Mark Hreish's practice location on file with NPPES is 10800 Magnolia Ave, Riverside, CA 92505-3043.
- What is Mark Hreish's phone number?
- The practice phone number listed in the NPPES registry for Mark Hreish is (951) 353-2000.
- Does Mark Hreish accept Medicare?
- Mark Hreish is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Mark Hreish's NPI active?
- Yes — Mark Hreish's NPI (1164839502) is active in the NPPES registry as of the last update on 2021-12-01.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.