Zachary Gerard O'Leary, PA-C

Physician Assistant

Zachary Gerard O'Leary is a Physician Assistant based in Castro Valley, CA with over 5 years of clinical experience. Medicare-enrolled per CMS records and offers virtual telehealth visits.

(888) 924-1036Castro Valley, CA
Telehealth Available
NPI Active per CMS — Q2 2026|Medicare Enrolled|Order & Refer

Zachary Gerard O'Leary, PA-C practices as part of a group physician assistant practice in Castro Valley, CA. He completed training at Stanford University School of Medicine in 2021 and is early in his career. A physician assistant is a person who has successfully completed an accredited education program for physician assistant. CMS MIPS quality score: 94.91/100 (2023).

At a glance

  • Prescribes opioids less than 46% of reporting doctors in California
  • Uses generic medications more than 36% of reporting doctors in California
  • Federal MIPS score higher than 80% of MIPS-scored doctors in California
  • Virtual visits available — no app or travel required
1 of 1,621 Physician Assistant providers in CASee all Physician Assistant in Castro Valley5+ years experienceNPI since 2021

Older · 908dNPPES updated 2023-11-28 · verify NPI on CMS · Verify license at Medical Board of California

Contact & Location

Practice Location

20642 John Dr, Castro Valley, CA 94546-5103

CMS Clinical Data

How Does This Doctor Compare?

Based on Medicare data, this doctor scores better than 80% of doctors in California on federal quality measures, prescribes opioid pain medications conservatively, favors affordable generic drugs over brand-name ones.

MIPS Score

2023

94.91/100

California avg: 78.6 · US avg: 83.6

Higher than most doctors nationally(+11.3 pts)

Better than 80% of MIPS-scored doctors in California

How the government rates this doctor's Medicare care quality. Scores above 75 are considered good.

Opioid Rx

↓ Lower = better

1.26%

California avg: 5.2 · US avg: 5.1

Higher than most doctors nationally(-3.8 pts)

Typical range among reporting doctors in California

1.26% of this doctor's prescriptions are opioid pain medications. Lower means more cautious prescribing.

Generic Rx

↑ Higher = better

84.7%

California avg: 83.3 · US avg: 82.8

Higher than most doctors nationally(+1.9 pts)

How often this doctor prescribes affordable generic drugs instead of expensive brand-name ones.

Prescription Recipients

465

Patients prescribed

Prescriptions Written

1,904

Total claims

Total Medicare drug cost: $289k

Percentile rankings compared against 9,360 reporting peers in California.

Data Note: Sourced from CMS Medicare Provider Utilization & Payment Data. Percentile rankings compare this provider against all peers with reported data in the same state. Updated annually to reflect the latest federal reporting cycle.

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Background & Specialty

Education, training, and specialty classification from CMS NPPES and Medicare records.

Career Journey
  1. Graduated medical school · 2021

    Stanford University School of Medicine

  2. Board certified · Nov 27, 2023

    Self-reported via NPPES

  3. 5 years in practice

    Established

Physician AssistantPhysician Assistants & Advanced Practice Nursing Providers

A physician assistant is a person who has successfully completed an accredited education program for physician assistant, is licensed by the state and is practicing within the scope of that license. Physician assistants are formally trained to perform many of the routine, time-consuming tasks a physician can do. In some states, they may prescribe medications. They take medical histories, perform physical exams, order lab tests and x-rays, and give inoculations. Most states require that they work under the supervision of a physician.

Taxonomy: 363A00000X

Education & Training

Stanford University School of Medicine (Class of 2021)

Practice Footprint

Primary hospital affiliation: Psychiatric

CMS Certification Number: 194022

View hospital on Medicare Care Compare

Virtual Medical Care With Zachary Gerard O'Leary

NPPES records indicate this provider offers telehealth services. Contact the office to confirm availability and scheduling.

Schedule a virtual visit with Zachary Gerard O'Leary for follow-ups, medication reviews, and ongoing care — no travel to Castro Valley required. The office sends a secure video link before your appointment. Most visits take 15–30 minutes. Medicare enrolled per CMS records.

Frequently Asked Questions

Common questions about Zachary Gerard O'Leary

NPI records show Dr. O'Leary as active with telehealth listed in Castro Valley, CA. NPI status alone doesn't confirm open availability — call the office to confirm. Phone: (888) 924-1036.

Verified across 4 federal data sources

Sourced from CMS NPPES · OIG LEIE · CMS QPP 2023 · CMS Medicare Part D. See Data Methodology.

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Medical Disclaimer: NPI Telehealth is a provider directory for informational purposes only. This page does not constitute medical advice, diagnosis, or treatment recommendations. Provider data is sourced from the CMS NPPES federal registry and public Medicare datasets. NPI Telehealth does not verify clinical qualifications beyond federal records. Data may not reflect real-time availability — always contact the provider's office directly to confirm details before seeking care.

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