Make An Appointment

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

Family Practice Physician Eric Miller, DO, practices full time in the MHP Medical Group. Growing up with a Pediatrician Mother and Farmer Father, Dr. Miller enjoys caring for families in a rural setting. He describes himself as more of a listener than a talker and enjoys hearing about a patient’s life experiences. In his free…

Gayle Johnson, ARNP

Family Practice

For more than 30 years, Gayle has been a caring nurse in Grinnell, Iowa. She joined Mahaska Health in November 2019 and has loved the Mahaska Health environment as she provides expert care to the community. The relationship she has with her patients is very important and patients know Gayle sees them as an individual…

Tonya Johannes, DNP, ARNP-BC

Tonya Johannes, DNP, ARNP-BC has been a nurse practitioner at Mahaska Health since 2016 and has served the healthcare field since 2003 in nursing home, hospital and clinical settings. Johannes grew up in Albia, IA and chose the medical field after spending an entire summer in a hospital helping to care for her grandmother. She…

Edward Hirl, MD

Family Practice

Ed Hirl, MD, has practiced in Oskaloosa for over 33 years and has more than 40 years of medical practice experience. Growing up on a small farm near Davenport, IA, Dr. Hirl wanted to find an occupation that allowed him to find fulfillment by, “being there,” to help others live healthier lives. Whether in preventing…