NPI registry status
Active
2026 NPPES data Rheumatology Physician NPI 1083803324 MD PC
Verify on CMS → Charles May, MD PC
Rheumatology Physician in Poulsbo, Washington.
This profile is drawn from the federal National Provider Identifier Registry (CMS NPPES), which lists more than 7 million U.S. healthcare providers - including 6,200 in Rheumatology Physician, 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
894
Medicare Part D claims · 222 beneficiaries · Rheumatology Physician avg: 2K
Generic prescribing
80%
generic claims · 19% 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
Charles May, MD PC filed 894 Medicare Part D claims in 2023 as a Rheumatology Physician in Poulsbo, Washington, prescribing 80% generic.
- 894
- Part D claims, 2023
- 80%
- 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.
Charles May, MD PC's Medicare Part D volume vs every U.S. prescriber
Total Medicare Part D claims, 2023, across all CMS prescribers nationally
894 Top 27% higher than 73% 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
◑
Board-eligible specialty (heuristic, not verified)
Charles May, MD PC practices in an ABMS-board-eligible specialty but we don't have enough CMS-participation signals to confirm active board-certified status. Consult CertificationMatters.org (the official ABMS public lookup).
What does the federal data show about Charles May, MD PC?
Quality data not reportedPrimary specialty
Rheumatology Physician
Medicare Part D claims
894 56% vs specialty avg
Specialty distribution in Washington
How Rheumatology Physician compares to other specialties among Washington 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 Rheumatology Physician. 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).
Charles May, MD PC appears in the CMS NPPES registry as a Rheumatology Physician provider holding MD PC credentials at 22180 OLYMPIC COLLEGE WAY, Poulsbo, WA, 98370, with a listed phone of (360) 779-4444. NPI 1083803324 was issued on 10/23/2007.
Medicare Part D records for calendar year 2023 show 894 prescription claims written by this provider, covering 222 Medicare beneficiaries and totaling roughly $761K in drug spend, split 19% brand-name and 80% generic by claim count.
Rheumatology Physician is a mid-sized specialty nationwide, with 6,200 enrolled providers across 52 states and an average of 2,054 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 | 1083803324 |
|---|---|
| Specialty | Rheumatology Physician |
| Credentials | MD PC |
| Gender | Male |
| NPI Issued | 10/23/2007 |
License & disciplinary context - Washington WMC 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 ~34K Washington medical licensees in 2023 - they are NOT specific to Charles May, MD PC. To verify Charles May, MD PC's current license status, search the WMC public license lookup directly, or check the Federation of State Medical Boards (FSMB) verification service.
88
Total board actions, Washington 2023
Across 85 cases
2.59
Actions per 1,000 licensees
Washington statewide rate
probation
Most common action type
31 cases
WMC 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 Washington disciplinary trends page. Cross-checked against FSMB U.S. Medical Regulatory Trends.
Brand vs generic prescribing mix · Typical
Charles May, MD PC - brand share 19.0%
Rheumatology Physician average
19% brand-name claims vs 80% generic, on 894 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.
894
Total Claims
$761K
Total Drug Cost
222
Medicare Beneficiaries
Prescribing Breakdown
- 30-Day Fills
- 2,016
- Total Day Supply
- 59,878
- Brand vs Generic
- 19% brand / 80% generic
- Brand Drug Cost
- $710K
- Generic Drug Cost
- $50K
Patient Demographics
- Average Patient Age
- 67.8 years
- Avg HCC Risk Score
- 1.65
- Gender Split
- 73% female / 27% male
- Age Distribution
- <65: 62, 65-74: 102, 75-84: N/A, 85+: N/A
Top Prescribed Drugs (Medicare Part D)
Top drugs by claim count for calendar year 2023. Based on Medicare Part D data only.
What Charles May, MD PC prescribes most
Top Medicare Part D drugs by claim count, 2023
- Hydroxychloroquine…
Hydroxychloroquine Sulfate
239 claims
- Methotrexate
Methotrexate
161 claims
- Leflunomide 91
Leflunomide
91 claims
- Prednisone 77
Prednisone
77 claims
- Cevimeline Hcl 29
Cevimeline Hcl
29 claims
- Enbrel Sureclick 25
Enbrel Sureclick
25 claims
- Folic Acid 23
Folic Acid
23 claims
- Humira(Cf) Pen 20
Humira(Cf) Pen
20 claims
| Drug | Claims |
|---|---|
| Hydroxychloroquine Sulfate | 239 |
| Methotrexate Methotrexate Sodium | 161 |
| Leflunomide | 91 |
| Prednisone | 77 |
| Cevimeline Hcl | 29 |
| Enbrel Sureclick Etanercept | 25 |
| Folic Acid | 23 |
| Humira(Cf) Pen Adalimumab | 20 |
| Sulfasalazine | 20 |
| Pilocarpine Hcl | 15 |
* Counts below 11 are suppressed by CMS for patient privacy. Generic names shown where available from CMS Part D data.
Rheumatology Physician Overview
How Charles May, MD PC fits within the Rheumatology Physician landscape nationally.
6,200
Rheumatology Physician Providers in US
52
States with Rheumatology Physician
2,054
Avg Claims per Provider
Charles May, MD PC's 894 claims are below the specialty average of 2,054.
Nearby Rheumatology Physician Providers in Washington
Other clinicians with the same primary specialty enrolled in Washington, drawn from the same CMS NPPES roster as May.
Dr. Jowairiyya Ahmad
M.D.
Lacey, WA
Dr. Hebatalla Allam
M.D.
Kennewick, WA
Dr. Brent Appleton
MD
Seattle, WA
Dr. Percy Balderia
MD
Seattle, WA
Dr. John Baldwin
MD
Bellevue, WA
Compare Rheumatology Physician 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 Washington medical board, federal registration is not a license check. Credential verification guide
- Weigh a second option: compare this provider with a nearby Rheumatology Physician 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 Charles May, MD PC's specialty? ▼
Charles May, MD PC specializes in Rheumatology Physician and practices in Poulsbo, Washington. Credentials: MD PC.
How much does Charles May, MD PC prescribe under Medicare Part D? ▼
In 2023, Charles May, MD PC wrote 894 Medicare Part D claims totaling $761K in drug costs for 222 beneficiaries.
Where is Charles May, MD PC located? ▼
Charles May, MD PC is located at 22180 OLYMPIC COLLEGE WAY, Poulsbo, WA, 98370. Phone: (360) 779-4444.
What is Charles May, MD PC's NPI number? ▼
Charles May, MD PC's National Provider Identifier (NPI) is 1083803324, issued on 10/23/2007.
Does Charles May, MD PC prescribe more brand-name or generic drugs? ▼
Charles May, MD PC's prescribing is 19% brand-name and 80% generic drugs by claim count, with $710K in brand drug costs.
How many Rheumatology Physician providers are there in the US? ▼
There are 6,200 Rheumatology Physician providers across 52 states in the US. The average Rheumatology Physician provider writes 2,054 Medicare Part D claims per year.
What drugs does Charles May, MD PC prescribe most often? ▼
Based on 2023 Medicare Part D data, Charles May, MD PC's most frequently prescribed drugs include Hydroxychloroquine Sulfate, Methotrexate, Leflunomide. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does Charles May, MD PC accept Medicare? ▼
Charles May, MD PC appears in CMS Medicare data with 894 Part D claims and 222 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify Charles May, MD PC's credentials? ▼
Charles May, MD PC's NPI is 1083803324 with credentials MD PC. 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.