2026 NPPES data Optometrist NPI 1245883297 OD
Verify on CMS →

MARK OSSI, OD

Optometrist in LEESBURG, Florida. CMS National Plan and Provider Enumeration System profile including specialty classification, practice address, and Medicare prescribing data when reported.

Federal data — no proprietary rating. PlainDoctor publishes the actual CMS NPPES and Medicare records — NPI registration, specialty, practice location, and prescribing data — without a composite score or editorial opinion on top. Every field traces to a federal source.
Prescribing volume
204
Medicare Part D claims · 42 beneficiaries · Optometrist avg: 257
Generic prescribing
64%
generic claims · 36% brand-name · higher generic rates reduce patient out-of-pocket costs

What the federal data shows

MARK OSSI, OD filed 204 Medicare Part D claims in 2023 as a Optometrist in LEESBURG, Florida, prescribing 64% generic.

204
Part D claims, 2023
64%
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.

MARK OSSI, OD's Medicare Part D volume vs every U.S. prescriber

Total Medicare Part D claims, 2023 — across all CMS prescribers nationally

204 49th percentile higher than 49% of 1,370,886 prescribers

0–200: 670,926 prescribers (49%). Below this entry. 200–400: 182,923 prescribers (13%). This entry sits in this band. 400–600: 90,619 prescribers (7%). Above this entry. 600–800: 56,224 prescribers (4%). Above this entry. 800–1,000: 40,919 prescribers (3%). Above this entry. 1,000–1,200: 31,827 prescribers (2%). Above this entry. 1,200–1,400: 26,224 prescribers (2%). Above this entry. 1,400–1,600: 21,710 prescribers (2%). Above this entry. 1,600–1,800: 19,072 prescribers (1%). Above this entry. 1,800–2,000: 16,451 prescribers (1%). Above this entry. 2,000–2,200: 213,991 prescribers (16%). Above this entry. This provider 0 2K+ every Part D prescriber (claims/yr), bucketed by value

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

What does the federal data show about MARK OSSI, OD?

Quality data not reported

NPI registry status

Active

Issued 07/18/2019

NPI 1245883297

Primary specialty

Optometrist

High-volume

60,463 US NPIs in this specialty

Medicare Part D claims

204 21% vs specialty avg

2023 prescription claims

Specialty avg: 257

Specialty distribution in Florida

How Optometrist compares to other specialties among Florida providers

Florida providers

Optometrist share within Florida

1. Optometrist42%2. Internal medicine21%3. Family medicine17%4. Surgical12%5. Pediatric8%
Optometrist share within Florida

Specialty board-certification context

Estimated specialty board-certified rate — Optometrist (ABMS / AOA reference)

Quality data not reported
Est. board-certified rate
78%
Optometrist ABMS/AOA estimate

Est. board-certified rate (Optometrist) — ABMS / AOA estimate

0%100%78%
Est. board-certified rate (Optometrist) — ABMS / AOA estimate

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).

MARK OSSI, OD appears in the CMS NPPES registry as a Optometrist provider holding OD credentials at 225 N 1ST ST, LEESBURG, FL, 34748, with a listed phone of (407) 905-8827. NPI 1245883297 was issued on 07/18/2019. Because NPPES data is self-reported by the provider and refreshed monthly, the address, phone, and specialty reflect what OSSI most recently submitted to CMS rather than a vetted directory listing, which is why patients should always confirm the practice is still at this location before scheduling.

Medicare Part D records for calendar year 2023 show 204 prescription claims written by this provider, covering 42 Medicare beneficiaries and totaling roughly $9K in drug spend, split 36% brand-name and 64% generic by claim count. These figures capture only Medicare Part D — commercial insurance, Medicaid, and cash-pay prescriptions are not included, and any drug-beneficiary cell under 11 is suppressed by CMS for patient privacy.

Optometrist is a high-volume specialty nationwide, with 60,463 enrolled providers across 56 states and an average of 257 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

225 N 1ST ST
LEESBURG, FL 34748

Provider Details

NPI 1245883297
Specialty Optometrist
Credentials OD
Gender Male
NPI Issued 07/18/2019

Hospital and facility affiliations

Facilities where MARK OSSI, OD 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.

COMMUNITY HEALTH CENTERS, INC
LEESBURG, FL

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 — Florida FLDOH 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 ~75K Florida medical licensees in 2023 — they are NOT specific to MARK OSSI, OD. To verify MARK OSSI, OD's current license status, search the FLDOH public license lookup directly, or check the Federation of State Medical Boards (FSMB) verification service.

480
Total board actions, Florida 2023
Across 467 cases
6.40
Actions per 1,000 licensees
Florida statewide rate
monetary fine
Most common action type
138 cases

FLDOH 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 Florida disciplinary trends page. Cross-checked against FSMB U.S. Medical Regulatory Trends.

Brand vs generic prescribing mix · Above average

MARK OSSI, OD — brand share 36.0%
Specialty average (est.)

36% brand-name claims vs 64% generic, on 204 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.

204
Total Claims
$9K
Total Drug Cost
42
Medicare Beneficiaries

Prescribing Breakdown

30-Day Fills
319
Total Day Supply
8,891
Brand vs Generic
36% brand / 64% generic
Brand Drug Cost
$7K
Generic Drug Cost
$2K

Patient Demographics

Average Patient Age
70.5 years
Avg HCC Risk Score
1.65
Gender Split
55% female / 45% male

Top Prescribed Drugs (Medicare Part D)

Top drugs by claim count for calendar year 2023. Based on Medicare Part D data only.

What MARK OSSI, OD prescribes most

Top Medicare Part D drugs by claim count, 2023

claims
Source CMS Medicare Part D Prescriber Public Use File As of 2023
Drug Claims
Latanoprost
92
Timolol Maleate
30
Dorzolamide Hcl
22
Brimonidine Tartrate
14
Olopatadine Hcl
13

* Counts below 11 are suppressed by CMS for patient privacy. Generic names shown where available from CMS Part D data.

Optometrist Overview

How MARK OSSI, OD fits within the Optometrist landscape nationally.

60,463
Optometrist Providers in US
56
States with Optometrist
257
Avg Claims per Provider

MARK OSSI, OD's 204 claims are below the specialty average of 257.

Nearby Optometrist Providers in Florida

Other clinicians with the same primary specialty enrolled in Florida, drawn from the same CMS NPPES roster as OSSI.

Compare Optometrist nationally: see state-by-state distribution →

Frequently Asked Questions

What is MARK OSSI, OD's specialty?
MARK OSSI, OD specializes in Optometrist and practices in LEESBURG, Florida. Credentials: OD.
How much does MARK OSSI, OD prescribe under Medicare Part D?
In 2023, MARK OSSI, OD wrote 204 Medicare Part D claims totaling $9K in drug costs for 42 beneficiaries.
Where is MARK OSSI, OD located?
MARK OSSI, OD is located at 225 N 1ST ST, LEESBURG, FL, 34748. Phone: (407) 905-8827.
What is MARK OSSI, OD's NPI number?
MARK OSSI, OD's National Provider Identifier (NPI) is 1245883297, issued on 07/18/2019.
Does MARK OSSI, OD prescribe more brand-name or generic drugs?
MARK OSSI, OD's prescribing is 36% brand-name and 64% generic drugs by claim count, with $7K in brand drug costs.
How many Optometrist providers are there in the US?
There are 60,463 Optometrist providers across 56 states in the US. The average Optometrist provider writes 257 Medicare Part D claims per year.
What drugs does MARK OSSI, OD prescribe most often?
Based on 2023 Medicare Part D data, MARK OSSI, OD's most frequently prescribed drugs include Latanoprost, Timolol Maleate, Dorzolamide Hcl. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does MARK OSSI, OD accept Medicare?
MARK OSSI, OD appears in CMS Medicare data with 204 Part D claims and 42 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify MARK OSSI, OD's credentials?
MARK OSSI, OD's NPI is 1245883297 with credentials OD. 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

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