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Pediatrics & Primary Care

Tonya Horn – ARNP. Tonya was born and raised in Iowa as an Oskaloosa native. She will begin serving patients at Mahaska Health as a Pediatric Nurse Practitioner after years of providing care for the community in our Emergency Room as an RN. Tonya started her nursing career in a Pediatric Intensive Care Unit and…

Family Practice, Obstetrics

Hannah Thompson is serving Mahaska Health as a Family Practice and Obstetrics Physician. Having grown up in the Midwest, Hannah is excited to begin serving Oskaloosa and the surrounding communities with her fellow residency peers, Drs. Preston Sereg and Eric Wood. Dr. Thompson treats her patients as she would treat her closest family members, bringing…

Family Practice, Obstetrics

Dr. Eric Wood – Family Practice & OB Physician will be serving the Oskaloosa community with his passion for treating rural Iowans with quality care, close to home! Eric is an Oklahoma native and was born and raised in a rural community, so Mahaska Health gives him that comfort of home! Eric chose to become…

Mark Zacharjasz, MD

Family Practice, Hospice

Dr. Mark Zacharjasz chose a career in family medicine due to his love of helping people and science. At Mahaska Health, Dr. Zacharjasz believes in offering his patients the best possible treatments and advice while upholding their values and autonomy. He accomplishes this by understanding each patient as a whole through the context of their…

Jess Tokle

Family Practice

Family Nurse Practitioner Jessica Tokle decided to go into medicine because she enjoys helping patients and learning from them. Originally from Grinnell, Jessica is excited to be close to home again. During her first year of college, she discovered her passion for nursing and decided to obtain her masters in nursing. Jessica received her Family…

Anna Throckmorton, ARNP

Anna Throckmorton, ARNP began serving as a nurse practitioner at Mahaska Health in September 2019. For many patients, Anna will be a familiar face as she has been a part of the Mahaska Health family for the past 15 years serving in various capacities, most recently as a registered nurse in the Birthing Center. Anna,…

Tara Stout, DNP, ARNP

Family Practice

Tara Stout, DNP, ARNP joined Mahaska Health in December 2019 after receiving her Doctorate of Nursing Practice from Clarke University in Dubuque, Iowa. Many may know her as she spent some time at Mahaska Health during her clinical rotations with Dr. O’Brien and Tonya Johannes. Tara grew up in Sully, Iowa and lives on a…

Shawn Richmond, MD

Family Practice, Obstetrics

Shawn Richmond, MD, has been serving the Mahaska Health community in areas of primary care and obstetrics since 2000. Originally, from Ottumwa, he chose to practice at Mahaska Health in order to be close to family and because of the great atmosphere of the community. Dr. Richmond is well known for the care and concern…

John O’Brien, MD

John O’Brien, MD specializes in the care of children from birth to 18 years of age and has been serving the Mahaska Health community since 2009. Originally from Chicago, O’Brien loved science from a young age and wanted to apply that love of science to his love for helping people. Dr. O’Brien chose pediatrics because…

Eric Miller, DO

Family Practice

Eric Miller, DO, has been with Mahaska Health since 2015. He grew up on a farm just outside Ottumwa, IA and chose Mahaska Health because he has always wanted to be close to home in a rural setting. Eric gravitated toward medicine since his mother is a Pediatrician, but he wanted to see a variety…