Medicare Part D Prescribers in Downey, California
7 flagged and high-volume prescribers across 4 medical specialties.
Data: CMS Medicare Part D, 2023 (most current available) · Updated March 2026
7
Providers
$16.5M
Total Drug Cost
1
High Risk
0.7%
Avg Opioid Rate
High-Risk Providers in Downey
Providers flagged by our multi-factor risk scoring model. Risk scores are statistical indicators, not allegations of wrongdoing. Learn about our methodology.
| Provider | Drug Cost | Opioid Rate |
|---|---|---|
| Domingo Barrientos | $3.0M | 0.5% |
Top Prescribers by Drug Cost
| Provider | Claims | Drug Cost |
|---|---|---|
| Shuo Zhou | 26,723 | $4.7M |
| Robert Wielenga | 26,597 | $3.9M |
| William Sim | 31,944 | $3.4M |
| Domingo BarrientosHigh Risk | 30,646 | $3.0M |
| Laura Ryan | 9,580 | $1.6M |
| Thu Phan | N/A | N/A |
| Mark Buchfuhrer | N/A | N/A |
Specialties in Downey
Internal Medicine
3 providers
Family Practice
2 providers
Nurse Practitioner
1 provider
Pulmonary Disease
1 provider
Explore More
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.