2026 NPPES data Infectious Disease Physician NPI 1235396235 MD
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SHILPA MARWAHA, MD

Infectious Disease Physician in NOVATO, California. 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
732
Medicare Part D claims · 403 beneficiaries · Infectious Disease Physician avg: 816
Generic prescribing
75%
generic claims · 25% brand-name · higher generic rates reduce patient out-of-pocket costs

What the federal data shows

SHILPA MARWAHA, MD filed 732 Medicare Part D claims in 2023 as a Infectious Disease Physician in NOVATO, California, prescribing 75% generic.

732
Part D claims, 2023
75%
generic prescribing
Likely
board-certified (heuristic)

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.

SHILPA MARWAHA, MD's Medicare Part D volume vs every U.S. prescriber

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

732 Top 29% higher than 71% of 1,370,886 prescribers

0–200: 670,926 prescribers (49%). Below this entry. 200–400: 182,923 prescribers (13%). Below this entry. 400–600: 90,619 prescribers (7%). Below this entry. 600–800: 56,224 prescribers (4%). This entry sits in this band. 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

Board certification likely (heuristic — not verified)

SHILPA MARWAHA, MD 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 SHILPA MARWAHA, MD?

Quality data not reported

NPI registry status

Active

Issued 05/19/2008

NPI 1235396235

Primary specialty

Infectious Disease Physician

Mid-sized

8,292 US NPIs in this specialty

Medicare Part D claims

732 10% vs specialty avg

2023 prescription claims

Specialty avg: 816

Specialty distribution in California

How Infectious Disease Physician compares to other specialties among California providers

California providers

Infectious Disease Physician share within California

1. Infectious Disease Physician42%2. Internal medicine21%3. Family medicine17%4. Surgical12%5. Pediatric8%
Infectious Disease Physician share within California

Specialty board-certification context

Estimated specialty board-certified rate — Infectious Disease Physician (ABMS / AOA reference)

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

Est. board-certified rate (Infectious Disease Physician) — ABMS / AOA estimate

0%100%78%
Est. board-certified rate (Infectious Disease Physician) — 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).

SHILPA MARWAHA, MD appears in the CMS NPPES registry as a Infectious Disease Physician provider holding MD credentials at 97 SAN MARIN DR, NOVATO, CA, 94945, with a listed phone of (415) 899-7400. NPI 1235396235 was issued on 05/19/2008. Because NPPES data is self-reported by the provider and refreshed monthly, the address, phone, and specialty reflect what MARWAHA 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 732 prescription claims written by this provider, covering 403 Medicare beneficiaries and totaling roughly $243K in drug spend, split 25% brand-name and 75% 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.

Infectious Disease Physician is a mid-sized specialty nationwide, with 8,292 enrolled providers across 54 states and an average of 816 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

97 SAN MARIN DR
NOVATO, CA 94945

Provider Details

NPI 1235396235
Specialty Infectious Disease Physician
Credentials MD
Gender Female
NPI Issued 05/19/2008

Hospital and facility affiliations

Facilities where SHILPA MARWAHA, 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.

PERMANENTE MEDICAL GROUP INC
VALLEJO, CA

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 — 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 SHILPA MARWAHA, MD. To verify SHILPA MARWAHA, MD'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 · Above average

SHILPA MARWAHA, MD — brand share 25.0%
Specialty average (est.)

25% brand-name claims vs 75% generic, on 732 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.

732
Total Claims
$243K
Total Drug Cost
403
Medicare Beneficiaries

Prescribing Breakdown

30-Day Fills
893
Total Day Supply
12,748
Brand vs Generic
25% brand / 75% generic
Brand Drug Cost
$223K
Generic Drug Cost
$20K
Antibiotic Claims
378

Patient Demographics

Average Patient Age
73.5 years
Avg HCC Risk Score
0.91
Gender Split
53% female / 47% male

Top Prescribed Drugs (Medicare Part D)

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

What SHILPA MARWAHA, MD 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
Azithromycin
280
Atovaquone-Proguanil Hcl
Atovaquone/Proguanil Hcl
120
Typhim Vi
Typhoid Vi Polysacch Vaccine
58
Havrix
Hepatitis A Virus Vaccine/Pf
46
Twinrix
Hepatitis A And B Vaccine/Pf
35
Doxycycline Monohydrate
27
Cefadroxil
20
Acetazolamide
18
Biktarvy
Bictegrav/Emtricit/Tenofov Ala
18
Sulfamethoxazole-Trimethoprim
Sulfamethoxazole/Trimethoprim
15

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

Infectious Disease Physician Overview

How SHILPA MARWAHA, MD fits within the Infectious Disease Physician landscape nationally.

8,292
Infectious Disease Physician Providers in US
54
States with Infectious Disease Physician
816
Avg Claims per Provider

SHILPA MARWAHA, MD's 732 claims are below the specialty average of 816.

Nearby Infectious Disease Physician Providers in California

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

Compare Infectious Disease Physician nationally: see state-by-state distribution →

Frequently Asked Questions

What is SHILPA MARWAHA, MD's specialty?
SHILPA MARWAHA, MD specializes in Infectious Disease Physician and practices in NOVATO, California. Credentials: MD.
How much does SHILPA MARWAHA, MD prescribe under Medicare Part D?
In 2023, SHILPA MARWAHA, MD wrote 732 Medicare Part D claims totaling $243K in drug costs for 403 beneficiaries.
Where is SHILPA MARWAHA, MD located?
SHILPA MARWAHA, MD is located at 97 SAN MARIN DR, NOVATO, CA, 94945. Phone: (415) 899-7400.
What is SHILPA MARWAHA, MD's NPI number?
SHILPA MARWAHA, MD's National Provider Identifier (NPI) is 1235396235, issued on 05/19/2008.
Does SHILPA MARWAHA, MD prescribe more brand-name or generic drugs?
SHILPA MARWAHA, MD's prescribing is 25% brand-name and 75% generic drugs by claim count, with $223K in brand drug costs.
How many Infectious Disease Physician providers are there in the US?
There are 8,292 Infectious Disease Physician providers across 54 states in the US. The average Infectious Disease Physician provider writes 816 Medicare Part D claims per year.
What drugs does SHILPA MARWAHA, MD prescribe most often?
Based on 2023 Medicare Part D data, SHILPA MARWAHA, MD's most frequently prescribed drugs include Azithromycin, Atovaquone-Proguanil Hcl, Typhim Vi. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does SHILPA MARWAHA, MD accept Medicare?
SHILPA MARWAHA, MD appears in CMS Medicare data with 732 Part D claims and 403 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify SHILPA MARWAHA, MD's credentials?
SHILPA MARWAHA, MD's NPI is 1235396235 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

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