NPI registry status
Active
2026 NPPES data Geriatric Medicine (Family Medicine) Physician NPI 1912055807 MD
Verify on CMS → Gary Birnbaum, MD
Geriatric Medicine (Family Medicine) Physician in San Diego, 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 1,779 in Geriatric Medicine (Family Medicine) 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
459
Medicare Part D claims · 46 beneficiaries · Geriatric Medicine (Family Medicine) Physician avg: 5K
Compiled from official public sources by the PlainDoctor editorial team.
What the federal data shows
Gary Birnbaum, MD filed 459 Medicare Part D claims in 2023 as a Geriatric Medicine (Family Medicine) Physician in San Diego, California.
- 459
- Part D claims, 2023
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.
Gary Birnbaum, MD's Medicare Part D volume vs every U.S. prescriber
Total Medicare Part D claims, 2023, across all CMS prescribers nationally
459 Top 38% higher than 62% of 1,370,886 prescribers
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)
Gary Birnbaum, MD 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 Gary Birnbaum, MD?
Quality data not reportedPrimary specialty
Geriatric Medicine (Family Medicine) Physician
Medicare Part D claims
459 91% vs specialty avg
Specialty distribution in California
How Geriatric Medicine (Family Medicine) Physician compares to other specialties among California 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 Geriatric Medicine (Family Medicine) 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).
Gary Birnbaum, MD appears in the CMS NPPES registry as a Geriatric Medicine (Family Medicine) Physician provider holding MD credentials at 4647 ZION AVE, San Diego, CA, 92120, with a listed phone of (619) 528-5000. NPI 1912055807 was issued on 01/08/2007.
Medicare Part D records for calendar year 2023 show 459 prescription claims written by this provider, covering 46 Medicare beneficiaries and totaling roughly $23K in drug spend, with an opioid prescribing rate of 5.2%.
Geriatric Medicine (Family Medicine) Physician is a narrow specialty nationwide, with 1,779 enrolled providers across 52 states and an average of 4,854 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
Provider Details
| NPI | 1912055807 |
|---|---|
| Specialty | Geriatric Medicine (Family Medicine) Physician |
| Credentials | MD |
| Gender | Male |
| NPI Issued | 01/08/2007 |
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 Gary Birnbaum, MD. To verify Gary Birnbaum, 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.
Medicare Part D Prescribing Data
CMS Medicare Part D prescriber-level data for calendar year 2023.
459
Total Claims
$23K
Total Drug Cost
46
Medicare Beneficiaries
Prescribing Breakdown
- 30-Day Fills
- 466
- Total Day Supply
- 11,932
- Generic Drug Cost
- $10K
- Opioid Claims
- 24 (5.2% rate)
Patient Demographics
- Average Patient Age
- 74.7 years
- Avg HCC Risk Score
- 2.72
- Gender Split
- 57% female / 43% male
Top Prescribed Drugs (Medicare Part D)
Top drugs by claim count for calendar year 2023. Based on Medicare Part D data only.
What Gary Birnbaum, MD prescribes most
Top Medicare Part D drugs by claim count, 2023
- Gabapentin
Gabapentin
34 claims
- Atorvastatin Calcium
Atorvastatin Calcium
27 claims
- Lisinopril
Lisinopril
23 claims
- Metoprolol Tartrate
Metoprolol Tartrate
22 claims
- Levetiracetam
Levetiracetam
21 claims
- Simvastatin
Simvastatin
20 claims
- Warfarin Sodium
Warfarin Sodium
15 claims
- Amlodipine Besylate 13
Amlodipine Besylate
13 claims
| Drug | Claims |
|---|---|
| Gabapentin | 34 |
| Atorvastatin Calcium | 27 |
| Lisinopril | 23 |
| Metoprolol Tartrate | 22 |
| Levetiracetam | 21 |
| Simvastatin | 20 |
| Warfarin Sodium | 15 |
| Amlodipine Besylate | 13 |
| Losartan Potassium | 13 |
| Sertraline Hcl | 13 |
* Counts below 11 are suppressed by CMS for patient privacy. Generic names shown where available from CMS Part D data.
More Geriatric Medicine (Family Medicine) Physician in CA →
All providers in California →
Compare specialties →
Geriatric Medicine (Family Medicine) Physician Overview
How Gary Birnbaum, MD fits within the Geriatric Medicine (Family Medicine) Physician landscape nationally.
1,779
Geriatric Medicine (Family Medicine) Physician Providers in US
52
States with Geriatric Medicine (Family Medicine) Physician
4,854
Avg Claims per Provider
Gary Birnbaum, MD's 459 claims are below the specialty average of 4,854.
Nearby Geriatric Medicine (Family Medicine) Physician Providers in California
Other clinicians with the same primary specialty enrolled in California, drawn from the same CMS NPPES roster as Birnbaum.
Dr. Nagina Abdiani
DO
Orange, CA
Dr. Shivali Agarwal
M.D.
Fresno, CA
Dr. Kent Ahn
MD
Fontana, CA
Dr. Theresa Allison
M.D.
San Francisco, CA
Dr. Nancy Alvarez
NP
Simi Valley, CA
Compare Geriatric Medicine (Family Medicine) 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 Geriatric Medicine (Family Medicine) 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.
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Frequently Asked Questions
What is Gary Birnbaum, MD's specialty? ▼
Gary Birnbaum, MD specializes in Geriatric Medicine (Family Medicine) Physician and practices in San Diego, California. Credentials: MD.
How much does Gary Birnbaum, MD prescribe under Medicare Part D? ▼
In 2023, Gary Birnbaum, MD wrote 459 Medicare Part D claims totaling $23K in drug costs for 46 beneficiaries.
Where is Gary Birnbaum, MD located? ▼
Gary Birnbaum, MD is located at 4647 ZION AVE, San Diego, CA, 92120. Phone: (619) 528-5000.
What is Gary Birnbaum, MD's NPI number? ▼
Gary Birnbaum, MD's National Provider Identifier (NPI) is 1912055807, issued on 01/08/2007.
Does Gary Birnbaum, MD prescribe opioids? ▼
Yes, Gary Birnbaum, MD had 24 opioid claims in 2023 with an opioid prescribing rate of 5.2%.
How many Geriatric Medicine (Family Medicine) Physician providers are there in the US? ▼
There are 1,779 Geriatric Medicine (Family Medicine) Physician providers across 52 states in the US. The average Geriatric Medicine (Family Medicine) Physician provider writes 4,854 Medicare Part D claims per year.
What drugs does Gary Birnbaum, MD prescribe most often? ▼
Based on 2023 Medicare Part D data, Gary Birnbaum, MD's most frequently prescribed drugs include Gabapentin, Atorvastatin Calcium, Lisinopril. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does Gary Birnbaum, MD accept Medicare? ▼
Gary Birnbaum, MD appears in CMS Medicare data with 459 Part D claims and 46 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify Gary Birnbaum, MD's credentials? ▼
Gary Birnbaum, MD's NPI is 1912055807 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 (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.