Parker Medical Center

Parker Medical CenterParker Medical CenterParker Medical Center
Home
Our Providers
Our Staff

Parker Medical Center

Parker Medical CenterParker Medical CenterParker Medical Center
Home
Our Providers
Our Staff
More
  • Home
  • Our Providers
  • Our Staff
  • Home
  • Our Providers
  • Our Staff

Our providers

Keith W. Shillito M.D.

As a Family Practice Physician with 25 years of experience, I take pride in caring for patients from childhood through senior years. My primary focus is on providing compassionate, comprehensive care to every family member. I am known for taking the time to listen.


I firmly believe in the bio-psycho-social model of medicine, where the whole patient is treated in context of their physical, mental and social well-being.


I took over Parker Medical Center from Dr. Marchese, a respected family physician, in 2004.


I enjoy birding, camping, hiking, nature and all my pets, from cats and cockatoos to snakes and turtles. I have a wonderful wife and a daughter who attends the University of Arizona. Many of my patients knew her when she was a baby.


Owner- Parker Medical Center, Ltd.

Board Certified- American Board of Family Medicine

Residency- Methodist/Mercy- Sacramento, California

Medical School- College of Human Medicine,      

Michigan State University- East Lansing, Michigan

Undergrad- University of California, Los Angeles- Los Angeles, California


Sandra G. Matheny DNP, AGNP-C

I joined Parker Medical Center in 2025. I started in healthcare as a nurse working in the Neuro ICU. I wanted to do more for people, so I applied to ASU's DNP program and started my nurse practitioner (NP) career in primary care and hematology.  


My favorite part of being a nurse practitioner is really connecting with people to help them achieve their goals. This allows me to easily empathize and work together with them to conquer challenges. I specialize in care for adults and seniors and enjoy listening to them so I can give them the best and most compassionate care possible.


I love animals, hiking, genealogy and genetics. I used to race bicycles, but now I'm happy just playing with my cute dogs. My favorite vacation spots are Hawaii for snorkeling with sea turtles and Europe for the amazing history.


Certified- Adult and Geriatric Medicine

Doctor of Nursing Practice- Arizona State University- Tempe, Arizona

Undergrad- University of Texas at Arlington- Arlington, Texas




Copyright © 2025 Parker Medical Center - All Rights Reserved.

Powered by

This website uses cookies.

We use cookies to analyze website traffic and optimize your website experience. By accepting our use of cookies, your data will be aggregated with all other user data.

Accept