NPI registry status
Active
2026 NPPES data Critical Care Medicine (Internal Medicine) Physician NPI 1891716072 M.D.
Verify on CMS → Christopher Fiack, M.D.
Critical Care Medicine (Internal Medicine) Physician in Honolulu, Hawaii.
This profile is drawn from the federal National Provider Identifier Registry (CMS NPPES), which lists more than 7 million U.S. healthcare providers - including 6,916 in Critical Care Medicine (Internal 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
655
Medicare Part D claims · 44 beneficiaries · Critical Care Medicine (Internal Medicine) Physician avg: 1K
Generic prescribing
59%
generic claims · 41% brand-name · higher generic rates reduce patient out-of-pocket costs
Source: CMS Medicare Part D Prescriber Public Use File, 2024
What the federal data shows
Christopher Fiack, M.D. filed 655 Medicare Part D claims in 2024 as a Critical Care Medicine (Internal Medicine) Physician in Honolulu, Hawaii, prescribing 59% generic.
- 655
- Part D claims, 2024
- 59%
- generic prescribing
- Likely
- board-certified (heuristic)
- ≥68th
- 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 Christopher Fiack, M.D.
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 1891716072), first enumerated 07/22/2006.
Source: CMS NPPES
- Reported
Medicare Part D participation
Filed 655 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
- 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 1891716072 · Critical Care Medicine (Internal Medicine) Physician
NPI-10 · ENUM-LEGACY · TAX-MID · RX-LIGHT · BOOK-THIN · PHOTO-ENUM
- NPI-10 1891716072
- ENUM-LEGACY 2006
- TAX-MID 7K Critical Care
- RX-LIGHT 655
- BOOK-THIN 31 in Hawaii
- PHOTO-ENUM Otto Schwarz, MD · 2006
Christopher Fiack, M.D.'s Medicare Part D volume vs every U.S. prescriber
Total Medicare Part D claims, 2024, across all CMS prescribers nationally
655 ≥ 68th percentile 68% 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)
Christopher Fiack, M.D. 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 Christopher Fiack, M.D.?
Quality data not reportedPrimary specialty
Critical Care Medicine (Internal Medicine) Physician
Medicare Part D claims
655 41% vs specialty avg
Specialty distribution in Hawaii
How Critical Care Medicine (Internal Medicine) Physician compares to other specialties among Hawaii 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 Critical Care Medicine (Internal Medicine) 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 | 1891716072 |
|---|---|
| Specialty | Critical Care Medicine (Internal Medicine) Physician |
| Credentials | M.D. |
| Gender | Male |
| NPI Issued | 07/22/2006 |
Hospital and facility affiliations
Facilities where Christopher Fiack, M.D. 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.
Queens University Medical Group
Honolulu, HI
Affiliations sourced from CMS Doctors and Clinicians National Downloadable File; hospital ratings from CMS Hospital General Information dataset (cross-referenced by facility name + state).
Brand vs generic prescribing mix · Above average
Christopher Fiack, M.D. - brand share 41.0%
Critical Care Medicine (Internal Medicine) Physician average
41% brand-name claims vs 59% generic, on 655 2024 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 2024.
655
Total Claims
$4.2M
Total Drug Cost
44
Medicare Beneficiaries
Prescribing Breakdown
- 30-Day Fills
- 729
- Total Day Supply
- 21,471
- Brand vs Generic
- 41% brand / 59% generic
- Brand Drug Cost
- $3.7M
- Generic Drug Cost
- $466K
Patient Demographics
- Average Patient Age
- 69.3 years
- Avg HCC Risk Score
- 2.35
- Gender Split
- 68% female / 32% male
- Age Distribution
- <65: 11, 65-74: 18, 75-84: N/A, 85+: N/A
Top Prescribed Drugs (Medicare Part D)
Top drugs by claim count for calendar year 2024. Based on Medicare Part D data only.
What Christopher Fiack, M.D. prescribes most
Top Medicare Part D drugs by claim count, 2024
- Sildenafil Citrate
Sildenafil Citrate
146 claims
- Opsumit
Opsumit
121 claims
- Ambrisentan
Ambrisentan
107 claims
- Tadalafil
Tadalafil
82 claims
- Tyvaso Dpi 45
Tyvaso Dpi
45 claims
- Orenitram Er 32
Orenitram Er
32 claims
- Adempas 23
Adempas
23 claims
- Albuterol Sulfate … 16
Albuterol Sulfate Hfa
16 claims
| Drug | Claims |
|---|---|
| Sildenafil Citrate | 146 |
| Opsumit Macitentan | 121 |
| Ambrisentan | 107 |
| Tadalafil | 82 |
| Tyvaso Dpi Treprostinil | 45 |
| Orenitram Er Treprostinil Diolamine | 32 |
| Adempas Riociguat | 23 |
| Albuterol Sulfate Hfa Albuterol Sulfate | 16 |
* Counts below 11 are suppressed by CMS for patient privacy. Generic names shown where available from CMS Part D data.
More Critical Care Medicine (Internal Medicine) Physician in HI →
All providers in Hawaii →
Compare specialties →
Critical Care Medicine (Internal Medicine) Physician Overview
How Christopher Fiack, M.D. fits within the Critical Care Medicine (Internal Medicine) Physician landscape nationally.
6,916
Critical Care Medicine (Internal Medicine) Physician Providers in US
53
States with Critical Care Medicine (Internal Medicine) Physician
1,103
Avg Claims per Provider
Christopher Fiack, M.D.'s 655 claims are below the specialty average of 1,103.
Nationwide Critical Care Medicine (Internal Medicine) Physician peers with similar MIPS or enrollment year
Two federal-record peer sets for Fiack, both outside Hawaii 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 Critical Care Medicine (Internal Medicine) Physician Providers in Hawaii
Other clinicians with the same primary specialty enrolled in Hawaii, drawn from the same CMS NPPES roster as Fiack.
One of 31 Critical Care Medicine (Internal Medicine) Physician providers enrolled in Hawaii, 5 are shown here.
Frequently Asked Questions
What is Christopher Fiack, M.D.'s specialty? ▼
Christopher Fiack, M.D. specializes in Critical Care Medicine (Internal Medicine) Physician and practices in Honolulu, Hawaii. Credentials: M.D..
How much does Christopher Fiack, M.D. prescribe under Medicare Part D? ▼
In 2024, Christopher Fiack, M.D. wrote 655 Medicare Part D claims totaling $4.2M in drug costs for 44 beneficiaries.
Where is Christopher Fiack, M.D. located? ▼
Christopher Fiack, M.D. is located at 1329 LUSITANA ST STE 107, Honolulu, HI, 96813. Phone: (808) 691-5252.
What is Christopher Fiack, M.D.'s NPI number? ▼
Christopher Fiack, M.D.'s National Provider Identifier (NPI) is 1891716072, issued on 07/22/2006.
Does Christopher Fiack, M.D. prescribe more brand-name or generic drugs? ▼
Christopher Fiack, M.D.'s prescribing is 41% brand-name and 59% generic drugs by claim count, with $3.7M in brand drug costs.
How many Critical Care Medicine (Internal Medicine) Physician providers are there in the US? ▼
There are 6,916 Critical Care Medicine (Internal Medicine) Physician providers across 53 states in the US. The average Critical Care Medicine (Internal Medicine) Physician provider writes 1,103 Medicare Part D claims per year.
What drugs does Christopher Fiack, M.D. prescribe most often? ▼
Based on 2024 Medicare Part D data, Christopher Fiack, M.D.'s most frequently prescribed drugs include Sildenafil Citrate, Opsumit, Ambrisentan. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does Christopher Fiack, M.D. accept Medicare? ▼
Christopher Fiack, M.D. appears in CMS Medicare data with 655 Part D claims and 44 Medicare beneficiaries in 2024. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify Christopher Fiack, M.D.'s credentials? ▼
Christopher Fiack, M.D.'s NPI is 1891716072 with credentials M.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 (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.