NPI registry status
Active
2026 NPPES data Psychiatry Physician NPI 1871555888 MD, PHD
Verify on CMS → John Denninger, MD, PHD
Psychiatry Physician in Boston, Massachusetts.
This profile is drawn from the federal National Provider Identifier Registry (CMS NPPES), which lists more than 7 million U.S. healthcare providers - including 54,383 in Psychiatry 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
181
Medicare Part D claims · 14 beneficiaries · Psychiatry Physician avg: 1K
What the federal data shows
John Denninger, MD, PHD filed 181 Medicare Part D claims in 2024 as a Psychiatry Physician in Boston, Massachusetts.
- 181
- Part D claims, 2024
- Likely
- board-certified (heuristic)
- ≥34th
- 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.
Federal trust snapshot
What official records show about John Denninger, MD, PHD
Federal records show an active NPI with Medicare Part D prescribing activity — verifiable registry data, not a proprietary rating.
- Verified
NPI registry status
Active listing in the CMS National Provider Identifier Registry (NPI 1871555888), first enumerated 04/05/2006.
Source: CMS NPPES
- Reported
Medicare Part D participation
Filed 181 Medicare Part D prescription claims in the 2023 CMS public use file — indicates active Medicare prescribing participation.
Source: CMS Part D Prescriber PUF
- Reported
Board certification signal
Heuristic suggests board-certified status based on ABMS-eligible specialty taxonomy plus active CMS participation signals — not a direct ABMS verification.
- Reported
Hospital affiliations
1 CMS Care Compare hospital affiliation on record — practice footprint from the Doctors and Clinicians file.
Source: CMS Care Compare
- State context
State board disciplinary context
Massachusetts statewide board action statistics are published annually — these figures describe aggregate state activity, not John Denninger, MD, PHD's individual license status. Verify directly with the state medical board.
Source: BORIM annual report 2023
- Not in federal data
Individual sanction lookup
PlainDoctor does not publish per-provider disciplinary determinations. Confirm current license and any individual actions through the state medical board or FSMB verification service.
Source: State medical board / FSMB
This trust snapshot summarizes only what appears in federal CMS/NPPES public records. It is not a composite score, star rating, patient review, or clinical recommendation. PlainDoctor never fabricates reviews or AggregateRating schema.
CMS NPPES provider registry desk
NPI 1871555888 · Psychiatry Physician
NPI-10 · ENUM-LEGACY · TAX-MEGA · RX-LIGHT · BOOK-LIGHT · PHOTO-ENUM
- NPI-10 1871555888
- ENUM-LEGACY 2006
- TAX-MEGA 54K Psychiatry Physician
- RX-LIGHT 181
- BOOK-LIGHT 2,637 in Massachusetts
- PHOTO-ENUM Enrico Camara, M.D. · 2006
John Denninger, MD, PHD's Medicare Part D volume vs every U.S. prescriber
Total Medicare Part D claims, 2024, across all CMS prescribers nationally
181 ≥ 34th percentile 34% of 1,416,883 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 · 2024
✓
Board certification likely (heuristic, not verified)
John Denninger, MD, PHD practices in an ABMS-board-eligible specialty and shows active CMS Medicare participation + 1 hospital affiliation - 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 John Denninger, MD, PHD?
Quality data not reportedPrimary specialty
Psychiatry Physician
Medicare Part D claims
181 82% vs specialty avg
Specialty distribution in Massachusetts
How Psychiatry Physician compares to other specialties among Massachusetts 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 Psychiatry 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).
Practice Address
Provider Details
| NPI | 1871555888 |
|---|---|
| Specialty | Psychiatry Physician |
| Credentials | MD, PHD |
| Gender | Male |
| NPI Issued | 04/05/2006 |
Hospital and facility affiliations
Facilities where John Denninger, MD, PHD bills Medicare from. Star ratings (1-5) are CMS Hospital Compare's "Hospital overall rating" - a composite of mortality, readmission, patient experience, safety, timely care, and efficient use of medical imaging measures. Source: CMS Care Compare.
Massachusetts General Physicians Organization Inc
Charlestown, MA
Affiliations sourced from CMS Doctors and Clinicians National Downloadable File; hospital ratings from CMS Hospital General Information dataset (cross-referenced by facility name + state).
License & disciplinary context - Massachusetts BORIM 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 ~38K Massachusetts medical licensees in 2023 - they are NOT specific to John Denninger, MD, PHD. To verify John Denninger, MD, PHD's current license status, search the BORIM public license lookup directly, or check the Federation of State Medical Boards (FSMB) verification service.
80
Total board actions, Massachusetts 2023
Across 78 cases
2.11
Actions per 1,000 licensees
Massachusetts statewide rate
probation
Most common action type
29 cases
BORIM 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 Massachusetts 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 2024.
181
Total Claims
$16K
Total Drug Cost
14
Medicare Beneficiaries
Prescribing Breakdown
- 30-Day Fills
- 418.333
- Total Day Supply
- 12,525
- Generic Drug Cost
- $8K
Patient Demographics
- Average Patient Age
- 69.4 years
- Avg HCC Risk Score
- 0.95
Top Prescribed Drugs (Medicare Part D)
Top drugs by claim count for calendar year 2024. Based on Medicare Part D data only.
What John Denninger, MD, PHD prescribes most
Top Medicare Part D drugs by claim count, 2024
- Methylphenidate Er
Methylphenidate Er
22 claims
- Duloxetine Hcl
Duloxetine Hcl
18 claims
- Lorazepam
Lorazepam
16 claims
- Buspirone Hcl
Buspirone Hcl
15 claims
- Venlafaxine Hcl Er
Venlafaxine Hcl Er
14 claims
- Aripiprazole
Aripiprazole
13 claims
- Clonazepam
Clonazepam
11 claims
| Drug | Claims |
|---|---|
| Methylphenidate Er Methylphenidate Hcl | 22 |
| Duloxetine Hcl | 18 |
| Lorazepam | 16 |
| Buspirone Hcl | 15 |
| Venlafaxine Hcl Er Venlafaxine Hcl | 14 |
| Aripiprazole | 13 |
| Clonazepam | 11 |
* Counts below 11 are suppressed by CMS for patient privacy. Generic names shown where available from CMS Part D data.
Psychiatry Physician Overview
How John Denninger, MD, PHD fits within the Psychiatry Physician landscape nationally.
54,383
Psychiatry Physician Providers in US
56
States with Psychiatry Physician
1,010
Avg Claims per Provider
John Denninger, MD, PHD's 181 claims are below the specialty average of 1,010.
Nationwide Psychiatry Physician peers with similar MIPS or enrollment year
Two federal-record peer sets for Denninger, both outside Massachusetts so the neighborhoods are not geographic containment.
Same NPPES enumeration year (2006)
Same-specialty clinicians who entered the NPI registry in the same calendar year, outside this state.
Nearby Psychiatry Physician Providers in Massachusetts
Other clinicians with the same primary specialty enrolled in Massachusetts, drawn from the same CMS NPPES roster as Denninger.
One of 2,637 Psychiatry Physician providers enrolled in Massachusetts, 5 are shown here.
Dr. Karen Abdool
M.D., PH.D
Lynn, MA
Dr. Harmony Abejuela
M.D.
Quincy, MA
Marielle Abell
PA
Amherst, MA
Dr. Steven Ablon
MD
Boston, MA
Dr. Keith Ablow
M.D.
Newbury, MA
Compare Psychiatry Physician nationally: see state-by-state distribution →
Frequently Asked Questions
What is John Denninger, MD, PHD's specialty? ▼
John Denninger, MD, PHD specializes in Psychiatry Physician and practices in Boston, Massachusetts. Credentials: MD, PHD.
How much does John Denninger, MD, PHD prescribe under Medicare Part D? ▼
In 2024, John Denninger, MD, PHD wrote 181 Medicare Part D claims totaling $16K in drug costs for 14 beneficiaries.
Where is John Denninger, MD, PHD located? ▼
John Denninger, MD, PHD is located at 50 STANIFORD ST STE 401, Boston, MA, 02114. Phone: (617) 726-2985.
What is John Denninger, MD, PHD's NPI number? ▼
John Denninger, MD, PHD's National Provider Identifier (NPI) is 1871555888, issued on 04/05/2006.
How many Psychiatry Physician providers are there in the US? ▼
There are 54,383 Psychiatry Physician providers across 56 states in the US. The average Psychiatry Physician provider writes 1,010 Medicare Part D claims per year.
What drugs does John Denninger, MD, PHD prescribe most often? ▼
Based on 2024 Medicare Part D data, John Denninger, MD, PHD's most frequently prescribed drugs include Methylphenidate Er, Duloxetine Hcl, Lorazepam. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does John Denninger, MD, PHD accept Medicare? ▼
John Denninger, MD, PHD appears in CMS Medicare data with 181 Part D claims and 14 Medicare beneficiaries in 2024. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify John Denninger, MD, PHD's credentials? ▼
John Denninger, MD, PHD's NPI is 1871555888 with credentials MD, PHD. 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 (2024). 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 August 2026 (NPPES) / 2024 (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 August 2026.