2026 NPPES data Allergy & Immunology Physician NPI 1205006657
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Natalie Cac

Allergy & Immunology Physician in Hayward, California.

This profile is drawn from the federal National Provider Identifier Registry (CMS NPPES), which lists more than 7 million U.S. healthcare providers - including 3,390 in Allergy & Immunology 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
116
Medicare Part D claims · 64 beneficiaries · Allergy & Immunology Physician avg: 764
Generic prescribing
81%
generic claims · 19% brand-name · higher generic rates reduce patient out-of-pocket costs
Compiled from official public sources by the PlainDoctor editorial team.

What the federal data shows

Natalie Cac filed 116 Medicare Part D claims in 2023 as a Allergy & Immunology Physician in Hayward, California, prescribing 81% generic.

116
Part D claims, 2023
81%
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.

Natalie Cac's Medicare Part D volume vs every U.S. prescriber

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

116 35th percentile higher than 35% of 1,370,886 prescribers

0–200: 670,926 prescribers (49%). This entry sits in this band. 200–400: 182,923 prescribers (13%). Above this entry. 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. 2K+: 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

Board-eligible specialty (heuristic, not verified)

Natalie Cac 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 Natalie Cac?

Quality data not reported

NPI registry status

Active

Issued 03/01/2008

NPI 1205006657

Primary specialty

Allergy & Immunology Physician

Niche

3,390 US NPIs in this specialty

Medicare Part D claims

116 85% vs specialty avg

2023 prescription claims

Specialty avg: 764

Specialty distribution in California

How Allergy & Immunology Physician compares to other specialties among California providers

California providers
Behavior Technician - 17.3%Behavior Technician17.3%Marriage & Family Therapist - 5.5%Marriage & Family Therapist5.5%Student in an Organized Health Care Education/Training Program - 5%Student in an Organized Health Care Education/Training Program5%Mental Health Counselor - 3.9%Mental Health Counselor3.9%Pharmacist - 3.5%Pharmacist3.5%Clinical Social Worker - 3.1%Clinical Social Worker3.1%Allergy & Immunology Physician - 0%Allergy & Immunology Physician0%
Largest specialties in California (% of in-state 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 Allergy & Immunology 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).

Natalie Cac appears in the CMS NPPES registry as a Allergy & Immunology Physician provider at 27303 SLEEPY HOLLOW AVE S, Hayward, CA, 94545, with a listed phone of (510) 784-6225. NPI 1205006657 was issued on 03/01/2008.

Medicare Part D records for calendar year 2023 show 116 prescription claims written by this provider, covering 64 Medicare beneficiaries and totaling roughly $15K in drug spend, split 19% brand-name and 81% generic by claim count.

Allergy & Immunology Physician is a narrow specialty nationwide, with 3,390 enrolled providers across 52 states and an average of 764 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

27303 SLEEPY HOLLOW AVE S
Hayward, CA 94545

Provider Details

NPI 1205006657
Specialty Allergy & Immunology Physician
Gender Female
NPI Issued 03/01/2008

License & disciplinary context - California MBC 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 ~150K California medical licensees in 2023 - they are NOT specific to Natalie Cac. To verify Natalie Cac's current license status, search the MBC public license lookup directly, or check the Federation of State Medical Boards (FSMB) verification service.

576
Total board actions, California 2023
Across 556 cases
3.84
Actions per 1,000 licensees
California statewide rate
probation
Most common action type
186 cases

MBC 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 California disciplinary trends page. Cross-checked against FSMB U.S. Medical Regulatory Trends.

Brand vs generic prescribing mix · Typical

Natalie Cac - brand share 19.0%
Allergy & Immunology Physician average

19% brand-name claims vs 81% generic, on 116 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.

116
Total Claims
$15K
Total Drug Cost
64
Medicare Beneficiaries

Prescribing Breakdown

30-Day Fills
169
Total Day Supply
4,748
Brand vs Generic
19% brand / 81% generic
Brand Drug Cost
$11K
Generic Drug Cost
$4K

Patient Demographics

Average Patient Age
73.6 years
Avg HCC Risk Score
1.11
Gender Split
66% female / 34% male

Top Prescribed Drugs (Medicare Part D)

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

Drug Claims
Azelastine Hcl
47
Ipratropium Bromide
25

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

Allergy & Immunology Physician Overview

How Natalie Cac fits within the Allergy & Immunology Physician landscape nationally.

3,390
Allergy & Immunology Physician Providers in US
52
States with Allergy & Immunology Physician
764
Avg Claims per Provider

Natalie Cac's 116 claims are below the specialty average of 764.

Nearby Allergy & Immunology Physician Providers in California

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

Compare Allergy & Immunology Physician nationally: see state-by-state distribution →

Before you book an appointment

Use this federal record as your verification checklist, not as a recommendation.

  • Confirm the NPI record is current in the official CMS registry, providers update their own NPPES details, and moves can lag. Verify this NPI
  • Check the active license and any disciplinary history with the California medical board, federal registration is not a license check. Credential verification guide
  • Weigh a second option: compare this provider with a nearby Allergy & Immunology Physician peer on Medicare volume and prescribing patterns. Compare providers

Medicare Part D and MIPS figures describe practice patterns in federal programs only, they are not quality ratings, and PlainDoctor does not rate, rank, or recommend providers.

Frequently Asked Questions

What is Natalie Cac's specialty?
Natalie Cac specializes in Allergy & Immunology Physician and practices in Hayward, California.
How much does Natalie Cac prescribe under Medicare Part D?
In 2023, Natalie Cac wrote 116 Medicare Part D claims totaling $15K in drug costs for 64 beneficiaries.
Where is Natalie Cac located?
Natalie Cac is located at 27303 SLEEPY HOLLOW AVE S, Hayward, CA, 94545. Phone: (510) 784-6225.
What is Natalie Cac's NPI number?
Natalie Cac's National Provider Identifier (NPI) is 1205006657, issued on 03/01/2008.
Does Natalie Cac prescribe more brand-name or generic drugs?
Natalie Cac's prescribing is 19% brand-name and 81% generic drugs by claim count, with $11K in brand drug costs.
How many Allergy & Immunology Physician providers are there in the US?
There are 3,390 Allergy & Immunology Physician providers across 52 states in the US. The average Allergy & Immunology Physician provider writes 764 Medicare Part D claims per year.
What drugs does Natalie Cac prescribe most often?
Based on 2023 Medicare Part D data, Natalie Cac's most frequently prescribed drugs include Azelastine Hcl, Ipratropium Bromide. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does Natalie Cac accept Medicare?
Natalie Cac appears in CMS Medicare data with 116 Part D claims and 64 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify Natalie Cac's credentials?
Natalie Cac's NPI is 1205006657. 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 (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

Compiled from official public sources by the PlainDoctor editorial team.