Medicare Part D Prescribers in San Jose, California

33 flagged and high-volume prescribers across 9 medical specialties.

Data: CMS Medicare Part D, 2023 (most current available) · Updated March 2026

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33

Providers

$43.5M

Total Drug Cost

2

High Risk

1.5%

Avg Opioid Rate

High-Risk Providers in San Jose

Providers flagged by our multi-factor risk scoring model. Risk scores are statistical indicators, not allegations of wrongdoing. Learn about our methodology.

ProviderDrug CostOpioid Rate
Donald Siao$1.1M4.9%
Zheng-Gang Zhang$10K0.0%

Top Prescribers by Drug Cost

ProviderClaimsDrug Cost
Ngoc Nguyen23,914$7.1M
Tung Nguyen46,948$6.4M
Joann Nguyen30,490$6.0M
Tam Nguyen27,524$3.9M
Dan Dang20,105$3.0M
Vinh Nguyen18,585$2.8M
Khanh Tran13,320$2.1M
Chistopher Do20,378$2.1M
Trang Do13,294$1.9M
Minh Huynh18,126$1.9M
Saman Sabounchi20,645$1.5M
Chung Vu13,273$1.4M
Timothy Ong10,181$1.2M
Donald SiaoHigh Risk9,590$1.1M
Jeanine Phan10,097$546K
Arunasri Kelleti1,936$272K
Assefa Worku4,953$213K
Zheng-Gang ZhangHigh Risk104$10K
Huong Thi Nguyen24$351
Nam Nguyen25$182

Specialties in San Jose

Internal Medicine

12 providers

Family Practice

4 providers

Dentist

2 providers

Ophthalmology

1 provider

Cardiology

1 provider

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Data from CMS Medicare Part D Prescriber Public Use File, 2023. Only providers meeting CMS disclosure thresholds are included. Risk scores are statistical indicators based on prescribing pattern analysis — not allegations of fraud or wrongdoing.