Nurse Practitioners

A Nurse Practitioner is a registered nurse who has completed advanced education and can offer many of the same services as a Doctor. SIMA Nurse Practitioners are independent of senior housing facilities and are affiliated with Sheboygan Internal Medicine Associates.

If you already have a doctor who is a member of the Sheboygan Internal Medicine Associates group, our Nurse Practitioners have complete access to your Doctor and medical files at our medical office. If you are looking for a Primary Care Doctor, SIMA would be pleased to welcome you as a new patient.

Doris U. Theune, APRN, BC

Doris began working with Sheboygan Internal Medicine Associates in May of 1991. She specializes in adult and geriatric care.

Doris received a Bachelor of Science in Nursing from the University of Wisconsin-Eau Claire in 1983. She then earned a Master of Science in 1990 from the University of Colorado at the Health Services Center in Denver, Colorado.

After completing her education, Doris served as a registered nurse in a variety of medical facilities and had the opportunity to round out her areas of experience.

Doris is licensed as a registered nurse by the state of Wisconsin and is certified by the American Nurses Credentialing Center as a geriatric nurse practitioner.

She enjoys reading, camping, travel, and spending time with her family. Doris lives in Sheboygan with her husband and two children.

Health promotion and maintenance are the two most important aspects of Doris’ practice.

Richard E. Mulhern, APRN, BC

Major, U.S. Army Retired

Richard began working with our group in December 1997. Richard enjoys the successes he shares with our patients involved in his anticoagulation clinic. His other interests include the exercise component in our healthy lifestyle classes, smoking cessation, and his daily work with our acute care patients.

Richard received his Bachelor of Science in Nursing from Northeast Louisiana University in Monroe, Louisiana in 1975. In 1976 he had a direct commission into the Army Nurse Corps. He received his adult nurse practitioner training at Selias B. Hayes Army Community Hospital at Ft. Ord, California in 1980 and was the honor graduate of the class. Richard was then selected to attend the Officers Advanced Course where he received training and further special education and emphasis in medical department management.

Richard has extensive experience gained at the wealth of medical facilities he served at during his duty with the Army.

Richard is certified by the American Nurses Credentialing Center. He is also certified as an Advanced Practice Nurse Prescriber and for basic cardiac life support by the American Heart Association. He is a member of the American Academy of Nurse Practitioners.

Making fine writing instruments and small wood working projects are the hobbies Richard enjoys.

Monica J. DeMuth, APRN, BC

Monica began working with our group in August of 2001. Her medical interests include smoking cessation and osteoporosis.

Monica received a Bachelor of Science in Nursing from the University of Wisconsin Madison in 1992. She then earned a Master of Science in Nursing from the University of Wisconsin-Milwaukee in 1999.

During the time Monica was completing her education, she served as a registered nurse at St. Luke’s Medical Center in Milwaukee. After earning her degrees, Monica was a nurse practitioner in Milwaukee.

Monica is certified as a family nurse practitioner by the American Nurses Credentialing Center. She is also licensed as an Advanced Practice Nurse Prescriber from the state of Wisconsin. Monica holds a controlled substance registration certificate from the Drug Enforcement Association, is trained to facilitate the American Lung Association’s Freedom from Smoking program, and is certified by the International Society of Clinical Densitometry to perform bone density testing.

Nicole L. Steinhardt, FNP-BC

Niki earned a Master of Science in Nursing from Concordia University in Mequon, WI. She is certified as a family nurse practitioner (FNP-BC) by the American Nurses Credentialing Center, is certified in advanced cardiac life support, is nationally registered as an Emergency Medical Technician-Basic, and is certified as a trauma nurse.

Theresa Brosnan-Schuler, ANP-BC

Theresa earned a Master of Science in Nursing from Marquette University in Milwaukee, Wisconsin. She is certified as an adult nurse practitioner (ANP-BC) by the American Nurses Credentialing Center, holds a controlled substance registration certificate from the Drug Enforcement Association, and is certified as an Advance Diabetes Manager.