NPI registry status
Active
2026 NPPES data Pain Medicine Physician NPI 1619991643 MD
Verify on CMS → Michael Castillo, MD
Pain Medicine Physician in Glendale, Arizona.
This profile is drawn from the federal National Provider Identifier Registry (CMS NPPES), which lists more than 7 million U.S. healthcare providers - including 952 in Pain Medicine 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
728
Medicare Part D claims · 135 beneficiaries · Pain Medicine Physician avg: 2K
Generic prescribing
93%
generic claims · 7% brand-name · higher generic rates reduce patient out-of-pocket costs
MIPS score
76/100
▼ 7 pts below national avg 83.1 · Above neutral
Source: CMS Medicare Part D Prescriber Public Use File, 2023
What the federal data shows
Michael Castillo, MD reported a CMS MIPS final score of 76/100 - below the 83.1 national average - and filed 728 Medicare Part D claims in 2023.
- 76/100
- MIPS score · -7 vs avg
- 728
- Part D claims, 2023
- 93%
- generic prescribing
- Likely
- board-certified (heuristic)
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.
Michael Castillo, MD's MIPS score vs every scored U.S. clinician
CMS Merit-based Incentive Payment System (MIPS) final score, 2023, the federal quality measure
76 15th percentile higher than 15% of 477,587 scored providers
Each bar is a band; taller bars hold more scored providers. 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 Merit-based Incentive Payment System (MIPS) · 2023
Where Michael Castillo, MD sits
This provider among pain medicine physician peers
Across the 286 pain medicine physician providers who report both Medicare Part D prescribing and a MIPS quality score, Michael Castillo, MD writes more Part D claims than 32% of them and scores higher on MIPS quality than 44% - placing this provider in the lower-volume, lower-quality quadrant. Volume reflects patient-panel size and specialty, not quality; the two axes are independent.
Part D claim volume vs MIPS quality, by specialty percentile
Each dot is one pain medicine physician peer from a representative sample of 60; the gold marker is Michael Castillo, MD. Source: CMS Medicare Part D Prescriber data and the CMS Merit-based Incentive Payment System, 2023.
✓
Board certification likely (heuristic, not verified)
Michael Castillo, MD practices in an ABMS-board-eligible specialty and shows active CMS Medicare participation + MIPS quality reporting - signals consistent with board-certified status. For verified board certification, see CertificationMatters.org (the official ABMS public lookup).
What does the federal data show about Michael Castillo, MD?
Below national averagePrimary specialty
Pain Medicine Physician
Medicare Part D claims
728 65% vs specialty avg
MIPS final score
76/100 7.1 pts vs avg
Specialty distribution in Arizona
How Pain Medicine Physician compares to other specialties among Arizona providers
Medicare quality performance, MIPS
Michael Castillo, MD's 2023 MIPS final score plotted against the Pain Medicine Physician national average
- MIPS Final Score
- 76/100
- vs 83.1 national avg · 2023 performance year
MIPS final score (Pain Medicine Physician) - 76/100 vs national avg 83.1
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).
Michael Castillo, MD appears in the CMS NPPES registry as a Pain Medicine Physician provider holding MD credentials at 5310 W THUNDERBIRD RD STE 215, Glendale, AZ, 85306, with a listed phone of (602) 242-9891. NPI 1619991643 was issued on 07/26/2006.
Medicare Part D records for calendar year 2023 show 728 prescription claims written by this provider, covering 135 Medicare beneficiaries and totaling roughly $42K in drug spend, split 7% brand-name and 93% generic by claim count, with an opioid prescribing rate of 65.4%. On the CMS Merit-based Incentive Payment System, this provider earned a Final Score of 76/100 for the 2023 performance year (Quality 56.3), compared with the national average of 83.1.
Pain Medicine Physician is a narrow specialty nationwide, with 952 enrolled providers across 49 states and an average of 2,078 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 | 1619991643 |
|---|---|
| Specialty | Pain Medicine Physician |
| Credentials | MD |
| Gender | Male |
| NPI Issued | 07/26/2006 |
CMS Quality Score (MIPS)
Merit-based Incentive Payment System (MIPS) scores from CMS, 2023 performance year.
75.9623
Final Score
Avg: 83.1
56.295
Quality
100
Promoting Interoperability
Reporting: Individual
Brand vs generic prescribing mix · Generic-heavy
Michael Castillo, MD - brand share 7.0%
Pain Medicine Physician average
7% brand-name claims vs 93% generic, on 728 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.
728
Total Claims
$42K
Total Drug Cost
135
Medicare Beneficiaries
Prescribing Breakdown
- 30-Day Fills
- 793
- Total Day Supply
- 20,922
- Brand vs Generic
- 7% brand / 93% generic
- Brand Drug Cost
- $27K
- Generic Drug Cost
- $15K
- Opioid Claims
- 476 (65.4% rate)
Patient Demographics
- Average Patient Age
- 70.0 years
- Avg HCC Risk Score
- 2.04
- Gender Split
- 56% female / 44% male
Top Prescribed Drugs (Medicare Part D)
Top drugs by claim count for calendar year 2023. Based on Medicare Part D data only.
What Michael Castillo, MD prescribes most
Top Medicare Part D drugs by claim count, 2023
- Oxycodone Hcl
Oxycodone Hcl
224 claims
- Gabapentin 63
Gabapentin
63 claims
- Hydrocodone-Acetam… 48
Hydrocodone-Acetaminophen
48 claims
- Oxycodone-Acetamin… 41
Oxycodone-Acetaminophen
41 claims
- Hydromorphone Hcl 39
Hydromorphone Hcl
39 claims
- Tramadol Hcl 33
Tramadol Hcl
33 claims
- Tizanidine Hcl 30
Tizanidine Hcl
30 claims
- Baclofen 29
Baclofen
29 claims
| Drug | Claims |
|---|---|
| Oxycodone Hcl | 224 |
| Gabapentin | 63 |
| Hydrocodone-Acetaminophen Hydrocodone/Acetaminophen | 48 |
| Oxycodone-Acetaminophen Oxycodone Hcl/Acetaminophen | 41 |
| Hydromorphone Hcl | 39 |
| Tramadol Hcl | 33 |
| Tizanidine Hcl | 30 |
| Baclofen | 29 |
| Diazepam | 27 |
| Morphine Sulfate | 25 |
* Counts below 11 are suppressed by CMS for patient privacy. Generic names shown where available from CMS Part D data.
Pain Medicine Physician Overview
How Michael Castillo, MD fits within the Pain Medicine Physician landscape nationally.
952
Pain Medicine Physician Providers in US
49
States with Pain Medicine Physician
2,078
Avg Claims per Provider
Michael Castillo, MD's 728 claims are below the specialty average of 2,078.
Nearby Pain Medicine Physician Providers in Arizona
Other clinicians with the same primary specialty enrolled in Arizona, drawn from the same CMS NPPES roster as Castillo.
Alfredo Bejarano
Phoenix, AZ
Dr. Eric Boyd
MD
Mesa, AZ
Dr. Tony Bui
M.D.
Phoenix, AZ
Dr. Jose Chavez
D.O.
Scottsdale, AZ
Dr. Azizat Dawodu
MD
Phoenix, AZ
Compare Pain Medicine 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 Arizona medical board, federal registration is not a license check. Credential verification guide
- Weigh a second option: compare this provider with a nearby Pain Medicine 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 Michael Castillo, MD's specialty? ▼
Michael Castillo, MD specializes in Pain Medicine Physician and practices in Glendale, Arizona. Credentials: MD.
How much does Michael Castillo, MD prescribe under Medicare Part D? ▼
In 2023, Michael Castillo, MD wrote 728 Medicare Part D claims totaling $42K in drug costs for 135 beneficiaries.
What is Michael Castillo, MD's Medicare quality score? ▼
Michael Castillo, MD has a CMS MIPS Final Score of 76/100 (Quality: 56.3). The national average MIPS Final Score is 83.1. Source: CMS Merit-based Incentive Payment System (MIPS) 2023.
Where is Michael Castillo, MD located? ▼
Michael Castillo, MD is located at 5310 W THUNDERBIRD RD STE 215, Glendale, AZ, 85306. Phone: (602) 242-9891.
What is Michael Castillo, MD's NPI number? ▼
Michael Castillo, MD's National Provider Identifier (NPI) is 1619991643, issued on 07/26/2006.
Does Michael Castillo, MD prescribe more brand-name or generic drugs? ▼
Michael Castillo, MD's prescribing is 7% brand-name and 93% generic drugs by claim count, with $27K in brand drug costs.
Does Michael Castillo, MD prescribe opioids? ▼
Yes, Michael Castillo, MD had 476 opioid claims in 2023 with an opioid prescribing rate of 65.4%.
How many Pain Medicine Physician providers are there in the US? ▼
There are 952 Pain Medicine Physician providers across 49 states in the US. The average Pain Medicine Physician provider writes 2,078 Medicare Part D claims per year.
What drugs does Michael Castillo, MD prescribe most often? ▼
Based on 2023 Medicare Part D data, Michael Castillo, MD's most frequently prescribed drugs include Oxycodone Hcl, Gabapentin, Hydrocodone-Acetaminophen. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does Michael Castillo, MD accept Medicare? ▼
Michael Castillo, MD appears in CMS Medicare data with 728 Part D claims and 135 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify Michael Castillo, MD's credentials? ▼
Michael Castillo, MD's NPI is 1619991643 with credentials MD. 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.
- Quality Performance
- CMS Merit-based Incentive Payment System (MIPS) - 2023 performance year.
- 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.