John R. Hayes, DO

Assistant Professor


  • Ascension Columbia St. Mary’s Milwaukee Family Health Center
  • 1121 E. North Avenue
  • Milwaukee, WI 53212


  • Family Medicine
  • Addiction Medicine

Columbia-St. Mary's Family Practice Center

My area of clinical focus has been providing primary care for “underserved” patients: People living with poverty, people with very low health literacy, people with substance use disorders, HIV, or Hep C, People with serious mental illness etc. These patients need intensive, culturally competent care in order to thrive. Unfortunately, I’ve found that many physicians lack the skill set to care for these psycho-socially complex patients. I got into medical education because I want to help under-served patients thrive by helping to train doctors that are properly equipped to care for them. My goal is to be the "one stop shop", providing comprehensive care for people that need the most help.


Diseases and Conditions

  • Bipolar Disorder
  • Depression and Anxiety Disorders
  • Hepatitis C
  • Chronic Pain
  • HIV
  • Complex Chronic Illness
  • Alcohol Use Disorder

Treatments and Services

  • Prenatal Care
  • Pediatrics
  • Osteopathic Manipulation Treatment
  • HIV Maintenance Medications
  • Hepatitis C Curative Treatments
  • Naltrexone (Vivitrol or Oral)
  • Buprenorphine (Suboxone, Sublocade)

Patients Ages Seen

  • Infant
  • Child
  • Adolescent
  • Adult
  • Senior


  • Spanish

Hospital Affiliations

  • Ascension Columbia St. Mary’s Hospital Milwaukee – Milwaukee

Board Certifications

  • Family Medicine
  • Addiction Medicine

Clinic Locations


After completing undergraduate education at Marquette University in Milwaukee, Wi, I leaned I had a strong interest in helping the medically underserved. In my undergraduate training, I led an organization called that brought healthcare to impoverished communities in Honduras. This inspired me to become a physician that focuses on providing care to the people that need it most. I completed medical education at Midwestern University and then residency at Northwestern’s Family Medicine program in Chicago. Residency was based out a federally qualified health center that cared for all patients, regardless of their ability to pay. During my training, I developed expertise in caring for opioid use disorder, HIV, and hepatitis C. I also discovered that I am passionate about medical education! I started my career as faculty at the Cook County Family Medicine Residency in Chicago. After starting a family, I decided to move back to Milwaukee and joined the Columbia St. Mary’s Family Medicine Residency. Since coming back to Milwaukee, I’ve become the Family medicine Clerkship Director at the Medical College of Wisconsin. I’ve also founded a thriving addiction medicine practice where we provide comprehensive care for patients suffering from opioid and alcohol use disorders.

Education and Training

Doctor of Osteopathic Medicine - Midwestern University - Downers Grove, IL (2013)
Residency in Family Medicine (with HIV are of concentration) - Northwestern University-McGaw Medical Center - Chicago, IL (2013-2016)