



A full spectrum of care.
ENT & Allergy Associates is North Central Wisconsin's most experienced and respected provider of ENT (ear, nose, and throat) and allergy/immunology/asthma services.
We are proud to have provided quality care to our Central Wisconsin communities for over 52 years!
Under one roof, we are able to offer a unique, collaborative approach to patient care. This allows both our pediatric and adult patients to receive care with unmatched excellence.
We offer the full spectrum of care and treatment of disorders related to ENT, Allergy, Immunology and Asthma.
In addition, our audiologists provide full diagnostic and treatment services to our hearing impaired patients, including hearing aid services.
Combined with our Wausau office, our additional satellite clinics provide accessibility to our patients throughout North Central Wisconsin.
At ENT & Allergy Associates, we pride ourselves in a comprehensive approach, integrating the highest degree of innovation with compassion.
Our new Wausau Clinic is an investment into our patients and our community.






Ear, Nose & Throat - Medical & Surgical
Mark A. Voss, M.D.
ENT | Ear, Nose & Throat
Board Certified by the American Board of Otolaryngology - Head and Neck Surgery
Treating Pediatric and Adult Patients
A native of Smith Center, Kansas, Dr. Voss graduated from the University of Colorado Health Sciences Medical School in 1991. He completed his Otolaryngology residency at the University of Colorado, Fitzsimons Army Medical Center in 1997 and served as the Chief of Otolaryngology Head and Neck Surgery at Bassett Army Hospital in Fort Wainwright, Alaska prior to arriving in Wausau.
Gregory K. Sewall, M.D.
ENT | Ear, Nose & Throat
Board Certified by the American Board of Otolaryngology - Head and Neck Surgery
Treating Pediatric and Adult Patients
A native of Fond du Lac, Wisconsin, Dr Sewall graduated from the Medical College of Wisconsin Medical School in 1999 and completed Otolaryngology residency at the University of Wisconsin Hospitals and Clinics in 2005. He is board certified by the American Board of Otolaryngology.
Jessica A. Weddle, D.O.
ENT | Ear, Nose & Throat
Board Certified by the American Board of Otolaryngology - Head and Neck Surgery
Board Certified by the American Academy of Facial Plastic and Reconstructive Surgery
Treating Pediatric and Adult Patients
A native of Monticello, Illinois, Dr. Weddle graduated from the Kansas City University of Medicine and Biosciences earning a Degree of Osteopathy in 2005. She completed residency training in Otolaryngology and Facial Plastic Surgery through the University of Michigan in 2010.
Sarvi S. Nalwa, M.D.
ENT | Ear, Nose & Throat
Board Certified by the American Board of Otolaryngology - Head and Neck Surgery
Treating Pediatric and Adult Patients
Dr. Nalwa received his Medical Doctorate at the University of Illinois, Chicago in 1996. His General Surgery residency was completed in 1997 and in 2001 he completed his Otolaryngology - Head and Neck Surgery residency, both at the University of Wisconsin, Madison.
Justin M. Hyde, M.D.
ENT | Ear, Nose & Throat
Board Certified by the American Board of Otolaryngology - Head and Neck Surgery
Treating Pediatric and Adult Patients
Dr. Hyde received his Medical Doctorate at the University of Mississippi School of Medicine, Jackson, MS in 2015. He completed his Otolaryngology, Head and Neck Surgery residency at the university of Virginia in Charlottesville, VA.
Lucas G. Leonhard, MD
ENT | Ear, Nose & Throat
Board Certified by the American Board of Otolaryngology - Head and Neck Surgery
Treating Pediatric and Adult Patients
A native of Marshfield, WI, Dr. Leonhard graduated from the University of Wisconsin School of Medicine & Public Health with a Doctor of Medicine Degree in 2016. He completed residency training in Otolaryngology - Head and Neck Surgery at the University of Wisconsin Hospital & Clinics.
Allergy, Asthma & Immunology
David A. Edmondson, D.O. FACP, FAAAAI
Allergy, Asthma & Immunology
Board Certified by the American Board of Allergy and Immunology
Treating Pediatric and Adult Patients
A native of Scottsdale, Arizona, Dr. Edmondson received his Doctor of Osteopathic Medicine degree from Western University of Health Sciences in Pomona, California. A residency in Internal Medicine was completed in 2004 at the Medical College of Wisconsin.
Todd L. Hostetler, M.D. FAAAAI
Allergy, Asthma & Immunology
Board Certified by the American Board of Allergy and Immunology
Treating Pediatric and Adult Patients
A native of Ohio, Dr. Hostetler graduated from The Ohio State University College of Medicine in 2004. He went on to complete a combined Internal Medicine and Pediatrics residency at The Ohio State University Medical Center and Nationwide Children’s Hospital in Columbus, Ohio.
Our Team of Physician Assistants
Chelsie R. Pagel, PA-C
Physician Assistant-Certified
Chelsie attended the University of Wisconsin, Madison where she received her Bachelor of Science, Medical Microbiology and Immunology degree in 2013. She received her Masters of Physician Assistant Studies at the University of Wisconsin School of Medicine and Public Health in 2017.
Brenda K. Balthazor, PA-C
Physician Assistant-Certified
Brenda received her Bachelor of Science in Medical Technology, Minor in Chemistry at the University of Wisconsin at Oshkosh, WI. She attended The University of Wisconsin Medical School at Madison, WI where she obtained her Bachelor of Science in Physician Assistant Studies in 2005.
In 2006 she received her Master of Physician Assistant Studies from the University of Nebraska Medical Center at Omaha, NE.
Nikolene D. Johnson, PA-C
Physician Assistant-Certified
A native of Tomahawk, Wisconsin, Nikolene attended Augsburg University where she received her Bachelors Degree in Biology with a minor in Chemistry and Psychology. She then went on to receive her Masters of Physician Assistant Studies from St. Catherine University in St. Paul, MN in 2016.
Hearing Center - Audiology
Katherine M. Klapperich
Au.D., CCC-A, FAAA
Audiologist
Dr. Katherine M. Klapperich received her Bachelor of Science Degree in Communicative Disorders from the University of Wisconsin-Stevens Point. She completed her audiology residency at Mayo Clinic Health System - Franciscan Healthcare in La Crosse, Wisconsin from 2011-2012.
Sarah C. Rosicky
Au.D., CCC-A, FAAA
Audiologist
Dr. Sarah Rosicky received her Bachelor of Science degree for Speech, Language, Hearing Sciences from Northern Michigan University in Marquette, MI. Dr. Rosicky obtained her Doctorate of Audiology from the joint audiology program between the University of Wisconsin – Stevens Point and Madison in 2018, graduating from the Stevens Point campus.
Chelsey N. Ward
Au.D., CCC-A, FAAA
Audiologist
Dr. Chelsey Ward completed her Bachelor of Science degree in Communicative Disorders from the University of Wisconsin – Stevens Point in 2015.
Emily K. Lohr
Au.D., FAAA
Audiologist
Dr. Emily K. Lohr received her Bachelor of Science Degree in Communication Sciences and Disorders from the University of Wisconsin - Eau Claire. Dr. Lohr obtained her Doctorate of Audiology from the joint audiology program between the University of Wisconsin - Stevens Point and Madison in 2015, graduating from the Madison campus.
Katherine R. Lipovetsky
Au.D., CCC-A, FAAA
Audiologist
Dr. Katherine R. Lipovetsky received her Bachelor of Arts Degree in Psychology and Linguistics from Montclair State University in Montclair, NJ. She completed her audiology residency at Virginia Commonwealth University (VCU) in Richmond, Virginia from 2020-2021.
Contact Us
Please call our Wausau Clinic for all appointments or questions.