Hien Nguyen, M.D.
NPI 1558591008 · Hospitalist Physician · Irvine, CA
Enrolled with Medicare as Practitioner - Hospitalist · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Hien Nguyen, M.D. is a Hospitalist Physician provider in Irvine, CA (NPI 1558591008).
Provider details
- NPI number
- 1558591008
- Entity type
- Individual
- Primary specialty
- Hospitalist PhysicianAllopathic & Osteopathic Physicians
- Credential
- M.D.
- Sex
- Female
- Sole proprietor
- No
- License
- A121257 (CA)
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
16 yrs in NPPES registry
- Profile completeness25% of score
100% of core fields populated
- Practice footprint15% of score
2 documented practice locations
- Medicare service volume (vs. specialty peers)25% of score
671 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) |
|---|---|---|
| Subsequent Hospital Care With Moderate Levelof Medical Decision Making, If Using Time, at Least 50 Minutes99233 | 254 | $119 |
| Subsequent Hospital Care With Moderate Levelof Medical Decision Making, If Using Time, at Least 35 Minutes99232 | 163 | $79 |
| Hospital Discharge Day Management, More Than 30 Minutes99239 | 112 | $117 |
| Initial Hospital Care With Moderate Level of Medical Decision Making, If Using Time, at Least 75 Minutes99223 | 94 | $172 |
| Initial Hospital Care With Straightforward Or Low-Level Medical Decision Making, If Using Time, at Least 55 Minutes99222 | 35 | $132 |
| Hospital Discharge Day Management, 30 Minutes Or Less99238 | 13 |
What this provider prescribes (Medicare Part D)
Top drugs by Medicare Part D claim volume, 2024 · 6 distinct drugs on file.
| Drug | Part D claims (2024) | Beneficiaries |
|---|---|---|
| Amoxicillin/Potassium Clavbrand: Amoxicillin-Clavulanate Potass | 20 | 20 |
| Atorvastatin Calcium | 17 | 14 |
| Cefdinir | 16 | 15 |
| Furosemide | 16 | 16 |
| Prednisone | 16 | 15 |
| Pantoprazole Sodium | 12 | 11 |
Medicare Part D only. These counts cover prescriptions paid through Medicare Part D in 2024 — they do notinclude 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.
Transparency — industry payments
Based on CMS Open Payments, 2024; not all care is captured.
$22 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
Additional practice locations (1)
- 16300 Sand Canyon Ave# 101-028Irvine, CA 92618-3711Phone: (888) 655-8463Fax: (866) 409-9349
Registry dates
- Enumerated
- 2009-07-18
- Last updated
- 2017-10-12
Frequently asked questions
- What is Hien Nguyen's NPI number?
- Hien Nguyen's National Provider Identifier (NPI) is 1558591008, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Hien Nguyen's specialty?
- Hien Nguyen is listed in the NPPES registry with a primary specialty of Hospitalist Physician (Allopathic & Osteopathic Physicians).
- Where is Hien Nguyen located?
- Hien Nguyen's practice location on file with NPPES is 16200 Sand Canyon Ave, Irvine, CA 92618-3714.
- What is Hien Nguyen's phone number?
- The practice phone number listed in the NPPES registry for Hien Nguyen is (949) 610-7245.
- Does Hien Nguyen accept Medicare?
- Hien Nguyen is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Hien Nguyen's NPI active?
- Yes — Hien Nguyen's NPI (1558591008) is active in the NPPES registry as of the last update on 2017-10-12.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.