NPI registry status
Active
2026 NPPES data Neurology Physician NPI 1518935964 M.D.
Verify on CMS → Gian Gierbolini, M.D.
Neurology Physician in Manati, Puerto Rico.
This profile is drawn from the federal National Provider Identifier Registry (CMS NPPES), which lists more than 7 million U.S. healthcare providers - including 20,467 in Neurology 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
3K
Medicare Part D claims · 348 beneficiaries · Neurology Physician avg: 1K
Generic prescribing
93%
generic claims · 7% 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
Gian Gierbolini, M.D. filed 2,641 Medicare Part D claims in 2024 as a Neurology Physician in Manati, Puerto Rico, prescribing 93% generic.
- 3K
- Part D claims, 2024
- 93%
- generic prescribing
- ≥87th
- 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 Gian Gierbolini, 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 1518935964), first enumerated 03/10/2006.
Source: CMS NPPES
- Reported
Medicare Part D participation
Filed 2,641 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
Practices in an ABMS-board-eligible specialty; board certification not confirmed in federal records.
- 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 1518935964 · Neurology Physician
NPI-10 · ENUM-LEGACY · TAX-MID · RX-MID · BOOK-THIN · PHOTO-ENUM
- NPI-10 1518935964
- ENUM-LEGACY 2006
- TAX-MID 20K Neurology Physician
- RX-MID 2,641
- BOOK-THIN 117 in Puerto Rico
- PHOTO-ENUM Kimberly Smith · 2006
Gian Gierbolini, M.D.'s Medicare Part D volume vs every U.S. prescriber
Total Medicare Part D claims, 2024, across all CMS prescribers nationally
2,641 ≥ 87th percentile 87% 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-eligible specialty (heuristic, not verified)
Gian Gierbolini, M.D. practices in an ABMS-board-eligible specialty but we don't have enough CMS-participation signals to confirm active board-certified status. Consult CertificationMatters.org (the official ABMS public lookup).
What does the federal data show about Gian Gierbolini, M.D.?
Quality data not reportedPrimary specialty
Neurology Physician
Medicare Part D claims
2,641 95% vs specialty avg
Specialty distribution in Puerto Rico
How Neurology Physician compares to other specialties among Puerto Rico 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 Neurology 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 | 1518935964 |
|---|---|
| Specialty | Neurology Physician |
| Credentials | M.D. |
| Gender | Male |
| NPI Issued | 03/10/2006 |
Brand vs generic prescribing mix · Generic-heavy
Gian Gierbolini, M.D. - brand share 7.0%
Neurology Physician average
7% brand-name claims vs 93% generic, on 2,641 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.
2,641
Total Claims
$697K
Total Drug Cost
348
Medicare Beneficiaries
Prescribing Breakdown
- 30-Day Fills
- 2,961.567
- Total Day Supply
- 87,448
- Brand vs Generic
- 7% brand / 93% generic
- Brand Drug Cost
- $611K
- Generic Drug Cost
- $85K
Patient Demographics
- Average Patient Age
- 75.0 years
- Avg HCC Risk Score
- 2.34
- Gender Split
- 54% female / 46% male
- Age Distribution
- <65: 47, 65-74: 87, 75-84: 162, 85+: 52
Top Prescribed Drugs (Medicare Part D)
Top drugs by claim count for calendar year 2024. Based on Medicare Part D data only.
What Gian Gierbolini, M.D. prescribes most
Top Medicare Part D drugs by claim count, 2024
- Donepezil Hcl
Donepezil Hcl
471 claims
- Memantine Hcl
Memantine Hcl
353 claims
- Carbidopa-Levodopa
Carbidopa-Levodopa
258 claims
- Divalproex Sodium Er
Divalproex Sodium Er
193 claims
- Levetiracetam 171
Levetiracetam
171 claims
- Pramipexole Dihydr… 148
Pramipexole Dihydrochloride
148 claims
- Gabapentin 111
Gabapentin
111 claims
- Rivastigmine 88
Rivastigmine
88 claims
| Drug | Claims |
|---|---|
| Donepezil Hcl | 471 |
| Memantine Hcl | 353 |
| Carbidopa-Levodopa Carbidopa/Levodopa | 258 |
| Divalproex Sodium Er Divalproex Sodium | 193 |
| Levetiracetam | 171 |
| Pramipexole Dihydrochloride Pramipexole Di-Hcl | 148 |
| Gabapentin | 111 |
| Rivastigmine | 88 |
| Escitalopram Oxalate | 85 |
| Carbidopa-Levodopa Er Carbidopa/Levodopa | 68 |
* Counts below 11 are suppressed by CMS for patient privacy. Generic names shown where available from CMS Part D data.
Neurology Physician Overview
How Gian Gierbolini, M.D. fits within the Neurology Physician landscape nationally.
20,467
Neurology Physician Providers in US
54
States with Neurology Physician
1,356
Avg Claims per Provider
Gian Gierbolini, M.D.'s 2,641 claims are above the specialty average of 1,356.
Nationwide Neurology Physician peers with similar MIPS or enrollment year
Two federal-record peer sets for Gierbolini, both outside Puerto Rico 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 Neurology Physician Providers in Puerto Rico
Other clinicians with the same primary specialty enrolled in Puerto Rico, drawn from the same CMS NPPES roster as Gierbolini.
One of 117 Neurology Physician providers enrolled in Puerto Rico, 5 are shown here.
Dr. Jose Acevedo
MD
Mayaguez, PR
Dr. Iris Acevedo-Marty
M.D.
Aguadilla, PR
Dr. Heriberto Acosta
M.D.
San Juan, PR
Dr. Marelisa Albelo Martinez
MD
San Juan, PR
Dr. Gishlaine Alfonso
MD
Hato Rey, PR
Compare Neurology Physician nationally: see state-by-state distribution →
Frequently Asked Questions
What is Gian Gierbolini, M.D.'s specialty? ▼
Gian Gierbolini, M.D. specializes in Neurology Physician and practices in Manati, Puerto Rico. Credentials: M.D..
How much does Gian Gierbolini, M.D. prescribe under Medicare Part D? ▼
In 2024, Gian Gierbolini, M.D. wrote 2,641 Medicare Part D claims totaling $697K in drug costs for 348 beneficiaries.
Where is Gian Gierbolini, M.D. located? ▼
Gian Gierbolini, M.D. is located at MANATI MEDICAL CENTER, Manati, PR, 00674. Phone: (787) 621-3737.
What is Gian Gierbolini, M.D.'s NPI number? ▼
Gian Gierbolini, M.D.'s National Provider Identifier (NPI) is 1518935964, issued on 03/10/2006.
Does Gian Gierbolini, M.D. prescribe more brand-name or generic drugs? ▼
Gian Gierbolini, M.D.'s prescribing is 7% brand-name and 93% generic drugs by claim count, with $611K in brand drug costs.
How many Neurology Physician providers are there in the US? ▼
There are 20,467 Neurology Physician providers across 54 states in the US. The average Neurology Physician provider writes 1,356 Medicare Part D claims per year.
What drugs does Gian Gierbolini, M.D. prescribe most often? ▼
Based on 2024 Medicare Part D data, Gian Gierbolini, M.D.'s most frequently prescribed drugs include Donepezil Hcl, Memantine Hcl, Carbidopa-Levodopa. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does Gian Gierbolini, M.D. accept Medicare? ▼
Gian Gierbolini, M.D. appears in CMS Medicare data with 2,641 Part D claims and 348 Medicare beneficiaries in 2024. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify Gian Gierbolini, M.D.'s credentials? ▼
Gian Gierbolini, M.D.'s NPI is 1518935964 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.