NPI registry status
Active
2026 NPPES data Ophthalmology Physician NPI 1285613273 MD
Verify on CMS → Mark Tannenbaum, MD
Ophthalmology Physician in Waterbury, Connecticut.
This profile is drawn from the federal National Provider Identifier Registry (CMS NPPES), which lists more than 7 million U.S. healthcare providers - including 22,388 in Ophthalmology 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
186
Medicare Part D claims · 61 beneficiaries · Ophthalmology Physician avg: 1K
Generic prescribing
72%
generic claims · 28% 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
Mark Tannenbaum, MD filed 186 Medicare Part D claims in 2024 as an Ophthalmology Physician in Waterbury, Connecticut, prescribing 72% generic.
- 186
- Part D claims, 2024
- 72%
- generic prescribing
- 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 Mark Tannenbaum, MD
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 1285613273), first enumerated 01/10/2006.
Source: CMS NPPES
- Reported
Medicare Part D participation
Filed 186 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
2 CMS Care Compare hospital affiliations 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 1285613273 · Ophthalmology Physician
NPI-10 · ENUM-LEGACY · TAX-MID · RX-LIGHT · BOOK-THIN · PHOTO-ENUM
- NPI-10 1285613273
- ENUM-LEGACY 2006
- TAX-MID 22K Ophthalmology Physician
- RX-LIGHT 186
- BOOK-THIN 347 in Connecticut
- PHOTO-ENUM Mark Siegel, M.D. · 2006
Mark Tannenbaum, MD's Medicare Part D volume vs every U.S. prescriber
Total Medicare Part D claims, 2024, across all CMS prescribers nationally
186 ≥ 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)
Mark Tannenbaum, MD practices in an ABMS-board-eligible specialty and shows active CMS Medicare participation + 2 hospital affiliations - 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 Mark Tannenbaum, MD?
Quality data not reportedPrimary specialty
Ophthalmology Physician
Medicare Part D claims
186 88% vs specialty avg
Specialty distribution in Connecticut
How Ophthalmology Physician compares to other specialties among Connecticut 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 Ophthalmology 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 | 1285613273 |
|---|---|
| Specialty | Ophthalmology Physician |
| Credentials | MD |
| Gender | Male |
| NPI Issued | 01/10/2006 |
Hospital and facility affiliations
Facilities where Mark Tannenbaum, MD 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.
Chinatown True Care Medical PLLC
New York, NY
Icahn School OF Medicine AT Mount Sinai
New York, NY
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
Mark Tannenbaum, MD - brand share 28.0%
Ophthalmology Physician average
28% brand-name claims vs 72% generic, on 186 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.
186
Total Claims
$24K
Total Drug Cost
61
Medicare Beneficiaries
Prescribing Breakdown
- 30-Day Fills
- 333.367
- Total Day Supply
- 9,683
- Brand vs Generic
- 28% brand / 72% generic
- Brand Drug Cost
- $16K
- Generic Drug Cost
- $8K
Patient Demographics
- Average Patient Age
- 73.2 years
- Avg HCC Risk Score
- 1.61
- Gender Split
- 56% female / 44% male
- Age Distribution
- <65: 11, 65-74: N/A, 75-84: 23, 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 Mark Tannenbaum, MD prescribes most
Top Medicare Part D drugs by claim count, 2024
- Latanoprost
Latanoprost
67 claims
- Dorzolamide-Timolol 25
Dorzolamide-Timolol
25 claims
- Methazolamide 18
Methazolamide
18 claims
- Combigan 11
Combigan
11 claims
| Drug | Claims |
|---|---|
| Latanoprost | 67 |
| Dorzolamide-Timolol Dorzolamide Hcl/Timolol Maleat | 25 |
| Methazolamide | 18 |
| Combigan Brimonidine Tartrate/Timolol | 11 |
* Counts below 11 are suppressed by CMS for patient privacy. Generic names shown where available from CMS Part D data.
Ophthalmology Physician Overview
How Mark Tannenbaum, MD fits within the Ophthalmology Physician landscape nationally.
22,388
Ophthalmology Physician Providers in US
56
States with Ophthalmology Physician
1,490
Avg Claims per Provider
Mark Tannenbaum, MD's 186 claims are below the specialty average of 1,490.
Nationwide Ophthalmology Physician peers with similar MIPS or enrollment year
Two federal-record peer sets for Tannenbaum, both outside Connecticut 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 Ophthalmology Physician Providers in Connecticut
Other clinicians with the same primary specialty enrolled in Connecticut, drawn from the same CMS NPPES roster as Tannenbaum.
One of 347 Ophthalmology Physician providers enrolled in Connecticut, 5 are shown here.
Dr. Marcio Abreu
M.D.
Bridgeport, CT
Dr. Bruce Altman
M.D.
Danbury, CT
Dr. Laura Andrews
MD
Waterbury, CT
Shimy Apoorva
Waterbury, CT
Dr. Yehuda Assouline
M.D.
Danbury, CT
Compare Ophthalmology Physician nationally: see state-by-state distribution →
Frequently Asked Questions
What is Mark Tannenbaum, MD's specialty? ▼
Mark Tannenbaum, MD specializes in Ophthalmology Physician and practices in Waterbury, Connecticut. Credentials: MD.
How much does Mark Tannenbaum, MD prescribe under Medicare Part D? ▼
In 2024, Mark Tannenbaum, MD wrote 186 Medicare Part D claims totaling $24K in drug costs for 61 beneficiaries.
Where is Mark Tannenbaum, MD located? ▼
Mark Tannenbaum, MD is located at 87 GRANDVIEW AVE, Waterbury, CT, 06708. Phone: (203) 574-2020.
What is Mark Tannenbaum, MD's NPI number? ▼
Mark Tannenbaum, MD's National Provider Identifier (NPI) is 1285613273, issued on 01/10/2006.
Does Mark Tannenbaum, MD prescribe more brand-name or generic drugs? ▼
Mark Tannenbaum, MD's prescribing is 28% brand-name and 72% generic drugs by claim count, with $16K in brand drug costs.
How many Ophthalmology Physician providers are there in the US? ▼
There are 22,388 Ophthalmology Physician providers across 56 states in the US. The average Ophthalmology Physician provider writes 1,490 Medicare Part D claims per year.
What drugs does Mark Tannenbaum, MD prescribe most often? ▼
Based on 2024 Medicare Part D data, Mark Tannenbaum, MD's most frequently prescribed drugs include Latanoprost, Dorzolamide-Timolol, Methazolamide. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does Mark Tannenbaum, MD accept Medicare? ▼
Mark Tannenbaum, MD appears in CMS Medicare data with 186 Part D claims and 61 Medicare beneficiaries in 2024. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify Mark Tannenbaum, MD's credentials? ▼
Mark Tannenbaum, MD's NPI is 1285613273 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 (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.