Board-certified in allergy and immunology, Gary C. Steven, MD, PhD, and Don A. Bukstein, MD and their staff operate a state-of-the-art allergy and asthma practice in southeastern Wisconsin. We provide the full range of allergy services for both children and adults.

The staff of the Allergy, Asthma & Sinus Center has worked hard to develop the facilities and expertise to meet the needs of all our allergy, asthma and sinus patients. We pride ourselves on meeting our patients’ individual needs, providing the highest quality of service and offering rapid appointment availability. Working as an independent clinic providing individual care, your quality of life is our greatest concern.


Dr. Steven received both his Bachelor of Science and Doctor of Philosophy degrees from the University of Wisconsin – Milwaukee and earned his medical degree from the Medical College of Wisconsin. After a residency in Internal Medicine, he completed a fellowship in Allergy and Immunology, both at the Medical College of Wisconsin.

Dr. Steven is board certified by the American Board of Allergy and Immunology and actively meets all maintenance of certification requirements for continuing education. He maintains leadership roles in both national allergy associations ‐ this includes service on the Board of Regents, Chair of the Accreditation & Certification committee and other committee participation with the American College of Allergy, Asthma & Immunology, as well as Medical Director of the AAAAI Registry along with additional committee participation with the American Academy of Allergy, Asthma & Immunology. He continues his committee participation with the World Allergy Organization, maintains his Certified Physician Investigator credential with the Association of Clinical Research Professionals, and is a Fellow of the Association of Physicians in Clinical Research.

Dr. Steven established the Allergy, Asthma & Sinus Center, S.C. as a solo, independent practice in February 2003 in order to continue to deliver high quality, comprehensive care without undue, external bureaucratic influences or expectations.

Recognized for his expertise in the field of allergy and asthma, Dr. Steven was selected by Milwaukee‐area physicians to Best Doctors in America®, a listing of the best 4% of US physicians. He has continued to receive this distinction since 2017.

A resident of New Berlin for 29 years, Dr. Steven lives with his wife Rene and has two children, two in‐laws, and is looking forward to grandchildren. In his leisure, he enjoys photography, scuba diving, home improvement and woodworking.

Dr. Bukstein received his Bachelor of Arts in English Literature from Tulane University in New Orleans, Louisiana and his medical degree cum laude from the University of Missouri – Columbia. He is triple board-certified in Allergy/Immunology, Pediatric Pulmonology and General Pediatrics. Dr. Bukstein served as Clinical Professor of Pediatric and Family Practice at the University of Wisconsin – Madison.

Dr. Bukstein is considered a national expert in the use of clinical outcomes managed by care, Continuing Medical Education (CME) and physical education using problem based learning (PBL). He has had over 100 articles/abstracts published in peer-reviewed journals. Dr. Bukstein was selected to “Best Doctors of the United States” and has been listed repeatedly in the Madison Magazine's "Madison's Best Doctors".

Dr. Bukstein is married with one daughter, four sons and a grandson. In his leisure time, he enjoys playing tennis, fishing, biking and attending UW – Madison sporting events.

Erica Landgraf received her Associate Degree of Nursing through Milwaukee Area Technical College. Once immersing herself as a medical nurse, she found a love for the profession and continued her training and education. She received her Bachelor's of Nursing degree through Alverno College, became a certified medical/surgical nurse, obtained her Master of Science in Nursing degree from Marion University and is now a certified Family Nurse Practitioner.

One of Erica's passions as a health care provider is education. She spent some time as a nursing instructor for Milwaukee School of Engineering and volunteered on a monthly basis to deliver up‐to‐date, holistic information on relevant health topics for the aging. The love for education has continued into her career here with Asthma, Allergy & Sinus Center where she obtained a certification as an Asthma Educator.

In 2012 and 2017, Erica was recognized by her peers for the Nurse Excellence award. She is a member of American Nurses Association as well as the American Association of Nurse Practitioners.

Free time is spent with her husband, Mike and their two younger sons who are all active in sports, mostly baseball. She also enjoys traveling, new experiences and a good meal with a good friend.