Ythanh Nguyen, MD
NPI 1255391181 · Internal Medicine Physician · Rancho Cucamonga, CA
Enrolled with Medicare as Practitioner - Internal Medicine · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Ythanh Nguyen, MD is a Internal Medicine Physician provider in Rancho Cucamonga, CA (NPI 1255391181).
Provider details
- NPI number
- 1255391181
- Entity type
- Individual
- Primary specialty
- Internal Medicine PhysicianAllopathic & Osteopathic Physicians
- Credential
- MD
- Sex
- Female
- Sole proprietor
- Yes
- License
- A84989 (CA)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure25% of score
20 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
618 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 | 301 | $118 |
| Established Patient Office Or Other Outpatient Visit With Moderate Level of Decision Making, If Using Time, 30 Minutes Or More99214 | 146 | $132 |
| Initial Hospital Care With Moderate Level of Medical Decision Making, If Using Time, at Least 75 Minutes99223 | 90 | $172 |
| Hospital Discharge Day Management, More Than 30 Minutes99239 | 81 | $115 |
Typical Medicare-allowed amounts for these services range $115–$172 (2024). The Medicare-allowed amount is what Medicare recognizes for a service under fee-for-service — a reference figure for 2024, not a price quote and not what you would be billed. Medicare Part B covers roughly an eighth of all NPIs (65+ skew); services with fewer than 11 beneficiaries are suppressed by CMS. Source: CMS Medicare Physician & Other Practitioners, by Provider & Service.
What this provider prescribes (Medicare Part D)
Top drugs by Medicare Part D claim volume, 2024 · 59 distinct drugs on file.
| Drug | Part D claims (2024) | Beneficiaries |
|---|---|---|
| Furosemide | 154 | 90 |
| Carvedilol | 87 | 54 |
| Levofloxacin | 71 | 66 |
| Atorvastatin Calcium | 68 | 40 |
| Apixabanbrand: Eliquis | 64 | 31 |
| Pantoprazole Sodium | 63 | 47 |
| Amlodipine Besylate | 61 | 40 |
Transparency — industry payments
Based on CMS Open Payments, 2024; not all care is captured.
$121 across 5 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
Additional practice locations (1)
- 999 San Bernardino RdSan Antonio Community HospitalUpland, CA 91786-4920Phone: (562) 236-3432Fax: (909) 944-5904
Registry dates
- Enumerated
- 2006-03-24
- Last updated
- 2025-12-14
- Certified
- 2025-12-14
Frequently asked questions
- What is Ythanh Nguyen's NPI number?
- Ythanh Nguyen's National Provider Identifier (NPI) is 1255391181, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Ythanh Nguyen's specialty?
- Ythanh Nguyen is listed in the NPPES registry with a primary specialty of Internal Medicine Physician (Allopathic & Osteopathic Physicians).
- Where is Ythanh Nguyen located?
- Ythanh Nguyen's practice location on file with NPPES is 8235 Rochester Ave, Rancho Cucamonga, CA 91730-0718.
- What is Ythanh Nguyen's phone number?
- The practice phone number listed in the NPPES registry for Ythanh Nguyen is (909) 484-4900.
- Does Ythanh Nguyen accept Medicare?
- Ythanh Nguyen is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Ythanh Nguyen's NPI active?
- Yes — Ythanh Nguyen's NPI (1255391181) is active in the NPPES registry as of the last update on 2025-12-14.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.