NPI registry status
Active
2026 NPPES data Ambulatory Care Pharmacist NPI 1477810174 PHARM.D.
Verify on CMS → Hannah Yoon, PHARM.D.
Ambulatory Care Pharmacist in Antioch, California.
This profile is drawn from the federal National Provider Identifier Registry (CMS NPPES), which lists more than 7 million U.S. healthcare providers - including 3,496 in Ambulatory Care Pharmacist, and covers specialty classification, practice address, and Medicare Part D prescribing data when reported. According to CMS, every field reflects the provider's official federal registration, see our methodology.
Federal data, no proprietary rating.
We show these CMS records as-is - no composite score, no star rating, no editorial opinion layered on top.
Prescribing volume
710
Medicare Part D claims · 392 beneficiaries · Ambulatory Care Pharmacist avg: 492
Generic prescribing
93%
generic claims · 7% brand-name · higher generic rates reduce patient out-of-pocket costs
Source: CMS Medicare Part D Prescriber Public Use File, 2023
Compiled from official public sources by the PlainDoctor editorial team.
What the federal data shows
Hannah Yoon, PHARM.D. filed 710 Medicare Part D claims in 2023 as a Ambulatory Care Pharmacist in Antioch, California, prescribing 93% generic.
- 710
- Part D claims, 2023
- 93%
- generic prescribing
Every figure on this page comes straight from federal CMS records (NPPES, Medicare Part D, MIPS, Open Payments) - no proprietary rating or editorial opinion is applied.
Hannah Yoon, PHARM.D.'s Medicare Part D volume vs every U.S. prescriber
Total Medicare Part D claims, 2023, across all CMS prescribers nationally
710 Top 29% higher than 71% of 1,370,886 prescribers
Each bar is a band; taller bars hold more prescribers. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count, share, and where it sits relative to this entry.
Source CMS Medicare Part D Prescriber Public Use File · 2023
What does the federal data show about Hannah Yoon, PHARM.D.?
Quality data not reportedPrimary specialty
Ambulatory Care Pharmacist
Medicare Part D claims
710 44% vs specialty avg
Specialty distribution in California
How Ambulatory Care Pharmacist compares to other specialties among California providers
Board certification
Not published by CMS
CMS does not publish a per-provider board-certification field in NPPES. PlainDoctor does not have a reliable per-specialty certification rate to show for Ambulatory Care Pharmacist. Verify directly:
How MIPS and board certification work
The Merit-based Incentive Payment System (MIPS) scores providers 0–100 across four performance categories: Quality, Cost, Promoting Interoperability, and Improvement Activities, weighted under 42 CFR §414.1380. Reporting is voluntary for many small practices, so absence of a MIPS score is not a quality signal.
Board certification through an ABMS or AOA member board signals voluntary post-licensure examination plus continuous Maintenance of Certification cycles. Verify any individual provider's status through certificationmatters.org (ABMS) or osteopathic.org (AOA).
Hannah Yoon, PHARM.D. appears in the CMS NPPES registry as an Ambulatory Care Pharmacist provider holding PHARM.D. credentials at 3454 HILLCREST AVE, Antioch, CA, 94531, with a listed phone of (925) 777-6300. NPI 1477810174 was issued on 04/19/2012.
Medicare Part D records for calendar year 2023 show 710 prescription claims written by this provider, covering 392 Medicare beneficiaries and totaling roughly $34K in drug spend, split 7% brand-name and 93% generic by claim count.
Ambulatory Care Pharmacist is a narrow specialty nationwide, with 3,496 enrolled providers across 52 states and an average of 492 Part D claims per prescriber, so the context for interpreting these metrics differs meaningfully from a primary-care baseline.
Important: PlainDoctor is a directory of publicly available government data, not medical advice, a malpractice database, or a quality rating. Inclusion here does not imply a recommendation, and absence of complaints or sanctions on this page does not mean none exist, always verify credentials through the NPPES NPI Registry, your state medical board, and the ABMS or AOA before making healthcare decisions.
Practice Address
Provider Details
| NPI | 1477810174 |
|---|---|
| Specialty | Ambulatory Care Pharmacist |
| Credentials | PHARM.D. |
| Gender | Female |
| NPI Issued | 04/19/2012 |
License & disciplinary context - California MBC 2023 annual report
Aggregate state board data only, NOT a determination of any individual provider's status. The figures below describe statewide disciplinary activity across all ~150K California medical licensees in 2023 - they are NOT specific to Hannah Yoon, PHARM.D.. To verify Hannah Yoon, PHARM.D.'s current license status, search the MBC public license lookup directly, or check the Federation of State Medical Boards (FSMB) verification service.
576
Total board actions, California 2023
Across 556 cases
3.84
Actions per 1,000 licensees
California statewide rate
probation
Most common action type
186 cases
MBC publishes annual disciplinary statistics as part of public-record reporting under each state's Administrative Procedure Act. See the full breakdown by action type and year on the California disciplinary trends page. Cross-checked against FSMB U.S. Medical Regulatory Trends.
Brand vs generic prescribing mix · Generic-heavy
Hannah Yoon, PHARM.D. - brand share 7.0%
Ambulatory Care Pharmacist average
7% brand-name claims vs 93% generic, on 710 2023 Medicare Part D claims.
The federal Medicare Part D Generic Dispensing Rate national benchmark sits near 90% generic / 10% brand for primary-care prescribers, per CMS Office of the Actuary 2024 estimates. Higher brand share is common in specialty prescribing where generic equivalents are not available.
Medicare Part D Prescribing Data
CMS Medicare Part D prescriber-level data for calendar year 2023.
710
Total Claims
$34K
Total Drug Cost
392
Medicare Beneficiaries
Prescribing Breakdown
- 30-Day Fills
- 1,187
- Total Day Supply
- 33,856
- Brand vs Generic
- 7% brand / 93% generic
- Brand Drug Cost
- $18K
- Generic Drug Cost
- $16K
Patient Demographics
- Average Patient Age
- 64.0 years
- Avg HCC Risk Score
- 1.31
- Gender Split
- 72% female / 28% male
- Age Distribution
- <65: 147, 65-74: 171, 75-84: 62, 85+: 12
Top Prescribed Drugs (Medicare Part D)
Top drugs by claim count for calendar year 2023. Based on Medicare Part D data only.
What Hannah Yoon, PHARM.D. prescribes most
Top Medicare Part D drugs by claim count, 2023
- Lorazepam
Lorazepam
82 claims
- Clonazepam
Clonazepam
44 claims
- Quetiapine Fumarate 30
Quetiapine Fumarate
30 claims
- Alprazolam 28
Alprazolam
28 claims
- Bupropion Xl 26
Bupropion Xl
26 claims
- Trazodone Hcl 26
Trazodone Hcl
26 claims
- Fluoxetine Hcl 25
Fluoxetine Hcl
25 claims
- Duloxetine Hcl 24
Duloxetine Hcl
24 claims
| Drug | Claims |
|---|---|
| Lorazepam | 82 |
| Clonazepam | 44 |
| Quetiapine Fumarate | 30 |
| Alprazolam | 28 |
| Bupropion Xl Bupropion Hcl | 26 |
| Trazodone Hcl | 26 |
| Fluoxetine Hcl | 25 |
| Duloxetine Hcl | 24 |
| Mirtazapine | 24 |
| Gabapentin | 22 |
* Counts below 11 are suppressed by CMS for patient privacy. Generic names shown where available from CMS Part D data.
Ambulatory Care Pharmacist Overview
How Hannah Yoon, PHARM.D. fits within the Ambulatory Care Pharmacist landscape nationally.
3,496
Ambulatory Care Pharmacist Providers in US
52
States with Ambulatory Care Pharmacist
492
Avg Claims per Provider
Hannah Yoon, PHARM.D.'s 710 claims are above the specialty average of 492.
Nearby Ambulatory Care Pharmacist Providers in California
Other clinicians with the same primary specialty enrolled in California, drawn from the same CMS NPPES roster as Yoon.
Clare Adams
Mission Viejo, CA
Kristine Adzhemyan
Los Angeles, CA
Dr. Omar Ahmed
PHARMD
San Rafael, CA
Dr. Soo Ahn
PHARM.D.
Simi Valley, CA
Dr. Genevieve Aichelman
PHARM.D.
Lemoore, CA
Compare Ambulatory Care Pharmacist nationally: see state-by-state distribution →
Before you book an appointment
Use this federal record as your verification checklist, not as a recommendation.
- Confirm the NPI record is current in the official CMS registry, providers update their own NPPES details, and moves can lag. Verify this NPI
- Check the active license and any disciplinary history with the California medical board, federal registration is not a license check. Credential verification guide
- Weigh a second option: compare this provider with a nearby Ambulatory Care Pharmacist peer on Medicare volume and prescribing patterns. Compare providers
Medicare Part D and MIPS figures describe practice patterns in federal programs only, they are not quality ratings, and PlainDoctor does not rate, rank, or recommend providers.
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Frequently Asked Questions
What is Hannah Yoon, PHARM.D.'s specialty? ▼
Hannah Yoon, PHARM.D. specializes in Ambulatory Care Pharmacist and practices in Antioch, California. Credentials: PHARM.D..
How much does Hannah Yoon, PHARM.D. prescribe under Medicare Part D? ▼
In 2023, Hannah Yoon, PHARM.D. wrote 710 Medicare Part D claims totaling $34K in drug costs for 392 beneficiaries.
Where is Hannah Yoon, PHARM.D. located? ▼
Hannah Yoon, PHARM.D. is located at 3454 HILLCREST AVE, Antioch, CA, 94531. Phone: (925) 777-6300.
What is Hannah Yoon, PHARM.D.'s NPI number? ▼
Hannah Yoon, PHARM.D.'s National Provider Identifier (NPI) is 1477810174, issued on 04/19/2012.
Does Hannah Yoon, PHARM.D. prescribe more brand-name or generic drugs? ▼
Hannah Yoon, PHARM.D.'s prescribing is 7% brand-name and 93% generic drugs by claim count, with $18K in brand drug costs.
How many Ambulatory Care Pharmacist providers are there in the US? ▼
There are 3,496 Ambulatory Care Pharmacist providers across 52 states in the US. The average Ambulatory Care Pharmacist provider writes 492 Medicare Part D claims per year.
What drugs does Hannah Yoon, PHARM.D. prescribe most often? ▼
Based on 2023 Medicare Part D data, Hannah Yoon, PHARM.D.'s most frequently prescribed drugs include Lorazepam, Clonazepam, Quetiapine Fumarate. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does Hannah Yoon, PHARM.D. accept Medicare? ▼
Hannah Yoon, PHARM.D. appears in CMS Medicare data with 710 Part D claims and 392 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify Hannah Yoon, PHARM.D.'s credentials? ▼
Hannah Yoon, PHARM.D.'s NPI is 1477810174 with credentials PHARM.D.. You can verify this through the NPPES NPI Registry, check state medical board records, and confirm board certification through the ABMS or AOA.
Data Sources
View source datasets and methodology notes
- Provider Directory
- CMS National Plan and Provider Enumeration System (NPPES), download.cms.gov/nppes, updated monthly. Contains NPI, specialty, credentials, and practice location.
- Specialty Classification
- NUCC Health Care Provider Taxonomy (nucc.org), the industry standard for classifying provider specialties in Medicare and Medicaid billing.
- Prescribing Data
- CMS Medicare Part D Prescriber Public Use File (2023). Includes claims, drug costs, beneficiaries, and opioid prescribing rates.
- Limitations
- Provider data is self-reported to CMS. Prescribing data reflects Medicare Part D only and does not include commercial insurance, Medicaid, or cash prescriptions. Claims below 11 beneficiaries are suppressed by CMS for privacy.
See our complete data methodology for details on how we collect and process government data.
Data as of April 2026 (NPPES) / 2023 (Medicare Part D). Source: Centers for Medicare & Medicaid Services (CMS).
Disclaimer: Data from CMS NPPES and Medicare Part D. PlainDoctor does not rate or rank providers. Provider information is self-reported and may not be current. Always verify information directly with the provider. About · Methodology
Compiled from official public sources by the PlainDoctor editorial team.
Every figure on PlainDoctor is rendered directly from the federal CMS NPPES registry, Medicare Part D, MIPS, and Open Payments records, no number is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of May 2026.