NPI registry status
Active
2026 NPPES data Physician Assistant NPI 1386341576 PA-C
Verify on CMS → Charmaine Santos, PA-C
Physician Assistant 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 150,974 in Physician Assistant, 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
625
Medicare Part D claims · 216 beneficiaries · Physician Assistant avg: 790
What the federal data shows
Charmaine Santos, PA-C filed 625 Medicare Part D claims in 2023 as a Physician Assistant in Antioch, California.
- 625
- Part D claims, 2023
- ≥69th
- pct by Part D claim volume (lower-bound band)
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.
Charmaine Santos, PA-C's Medicare Part D volume vs every U.S. prescriber
Total Medicare Part D claims, 2023, across all CMS prescribers nationally
625 ≥ 69th percentile 69% of 1,370,886 prescribers are in lower value bands
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.
The percentile is a conservative 100-claim band: it counts only prescribers in lower claim-volume bands. Medicare Part D claim volume is activity context, not a quality measure or recommendation. See methodology § corpus placement.
Source CMS Medicare Part D Prescriber Public Use File · 2023
What does the federal data show about Charmaine Santos, PA-C?
Quality data not reportedPrimary specialty
Physician Assistant
Medicare Part D claims
625 21% vs specialty avg
Specialty distribution in California
How Physician Assistant 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 Physician Assistant. 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).
Charmaine Santos, PA-C appears in the CMS NPPES registry as a Physician Assistant provider holding PA-C credentials at 3903 LONE TREE WAY STE 104, Antioch, CA, 94509, with a listed phone of (925) 755-1255. NPI 1386341576 was issued on 02/08/2023.
Medicare Part D records for calendar year 2023 show 625 prescription claims written by this provider, covering 216 Medicare beneficiaries and totaling roughly $74K in drug spend.
Physician Assistant is a high-volume specialty nationwide, with 150,974 enrolled providers across 56 states and an average of 790 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 | 1386341576 |
|---|---|
| Specialty | Physician Assistant |
| Credentials | PA-C |
| Gender | Female |
| NPI Issued | 02/08/2023 |
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 Charmaine Santos, PA-C. To verify Charmaine Santos, PA-C'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.
Medicare Part D Prescribing Data
CMS Medicare Part D prescriber-level data for calendar year 2023.
625
Total Claims
$74K
Total Drug Cost
216
Medicare Beneficiaries
Prescribing Breakdown
- 30-Day Fills
- 1,497
- Total Day Supply
- 43,464
- Generic Drug Cost
- $19K
- Antibiotic Claims
- 22
Patient Demographics
- Average Patient Age
- 73.3 years
- Avg HCC Risk Score
- 1.21
- Gender Split
- 61% female / 39% male
- Age Distribution
- <65: 24, 65-74: 86, 75-84: 76, 85+: 30
Top Prescribed Drugs (Medicare Part D)
Top drugs by claim count for calendar year 2023. Based on Medicare Part D data only.
What Charmaine Santos, PA-C prescribes most
Top Medicare Part D drugs by claim count, 2023
- Amlodipine Besylate
Amlodipine Besylate
35 claims
- Atorvastatin Calcium
Atorvastatin Calcium
35 claims
- Metoprolol Succinate
Metoprolol Succinate
34 claims
- Rosuvastatin Calcium
Rosuvastatin Calcium
32 claims
- Losartan Potassium
Losartan Potassium
29 claims
- Levothyroxine Sodium
Levothyroxine Sodium
24 claims
- Lisinopril
Lisinopril
16 claims
- Allopurinol
Allopurinol
14 claims
| Drug | Claims |
|---|---|
| Amlodipine Besylate | 35 |
| Atorvastatin Calcium | 35 |
| Metoprolol Succinate | 34 |
| Rosuvastatin Calcium | 32 |
| Losartan Potassium | 29 |
| Levothyroxine Sodium | 24 |
| Lisinopril | 16 |
| Allopurinol | 14 |
| Gabapentin | 14 |
| Olmesartan Medoxomil | 14 |
* Counts below 11 are suppressed by CMS for patient privacy. Generic names shown where available from CMS Part D data.
Physician Assistant Overview
How Charmaine Santos, PA-C fits within the Physician Assistant landscape nationally.
150,974
Physician Assistant Providers in US
56
States with Physician Assistant
790
Avg Claims per Provider
Charmaine Santos, PA-C's 625 claims are below the specialty average of 790.
Nearby Physician Assistant Providers in California
Other clinicians with the same primary specialty enrolled in California, drawn from the same CMS NPPES roster as Santos.
One of 13,402 Physician Assistant providers enrolled in California, 5 are shown here.
Dr. Marcia -Galbraith
PA
Stockton, CA
Dr. Danny Abad
PA
Orange, CA
Dr. Lea Dominique Abadies
PA
Tustin, CA
Dr. Rea Elizabeth Abaniel
P.A.-C
Seal Beach, CA
Dr. Ramina Abbasi
PA-C
Signal Hill, CA
Compare Physician Assistant 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 Physician Assistant 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 Charmaine Santos, PA-C's specialty? ▼
Charmaine Santos, PA-C specializes in Physician Assistant and practices in Antioch, California. Credentials: PA-C.
How much does Charmaine Santos, PA-C prescribe under Medicare Part D? ▼
In 2023, Charmaine Santos, PA-C wrote 625 Medicare Part D claims totaling $74K in drug costs for 216 beneficiaries.
Where is Charmaine Santos, PA-C located? ▼
Charmaine Santos, PA-C is located at 3903 LONE TREE WAY STE 104, Antioch, CA, 94509. Phone: (925) 755-1255.
What is Charmaine Santos, PA-C's NPI number? ▼
Charmaine Santos, PA-C's National Provider Identifier (NPI) is 1386341576, issued on 02/08/2023.
How many Physician Assistant providers are there in the US? ▼
There are 150,974 Physician Assistant providers across 56 states in the US. The average Physician Assistant provider writes 790 Medicare Part D claims per year.
What drugs does Charmaine Santos, PA-C prescribe most often? ▼
Based on 2023 Medicare Part D data, Charmaine Santos, PA-C's most frequently prescribed drugs include Amlodipine Besylate, Atorvastatin Calcium, Metoprolol Succinate. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does Charmaine Santos, PA-C accept Medicare? ▼
Charmaine Santos, PA-C appears in CMS Medicare data with 625 Part D claims and 216 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify Charmaine Santos, PA-C's credentials? ▼
Charmaine Santos, PA-C's NPI is 1386341576 with credentials PA-C. 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
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.