Meet Our Specialists

Meet Andrew C. Engler, M.D.

Andrew C. Engler, M.D. is the medical director of The Allergy and Asthma Clinic in San Mateo, California.

Dr. Engler received his Bachelor of Art degree, with distinction, from Stanford University in 1978. He was elected to the Phi Beta Kappa society when he was still a junior in college. After 2 years as a medical student at Yale, he returned to Stanford where he received his M.D. degree in 1982. He went on to complete his internship and residency at Stanford University Hospital and is Board Certified in Internal Medicine. Dr. Engler then received several years of additional training in Allergy, Asthma and Immunology. He founded The Allergy Clinic in San Mateo in 1987.

Dr. Engler is a member of many local, state and national professional organizations, including the American College of Allergy, Asthma & Immunology; the California Society of Allergy, Asthma & Immunology; the Joint Council on Allergy & Immunology; the Allergy Association of Northern California; the Asthma & Allergy Foundation of America; the California Medical Association and the San Mateo Medical Society.

Dr. Engler enjoys participating in a local journal club at which allergists from around the San Francisco Bay Area meet to review and discuss newly published medical articles of interest, usually in the field of allergy or asthma. (Dr. Engler is an avid reader and subscribes to many medical journals, including The Annals of Allergy, The Journal of Allergy and Clinical Immunology and The New England Journal of Medicine.) In addition to keeping his own knowledge base current, Dr. Engler feels it's important to help his colleagues in the community stay current on topics related to allergy and asthma. Dr. Engler has given a number of lectures to pediatricians, internists, and family physicians on issues related to treating allergies and asthma. Several years ago, Dr. Engler was honored to be voted one of the top physicians in the San Francisco Bay Area by an independent organization that rates physicians nationwide. The results were published in San Francisco Magazine.

Dr. Engler became interested in treating allergy early, since both his father and brother are also allergy specialists. His brother David is the medical director at The Allergy Clinic in Houston, Texas.

For over 20 years, since 1987, Dr. Engler has been treating patients with allergy, asthma and other related conditions. He lectures frequently and has a special interest in helping primary care physicians learn how to help their patients with allergies and asthma.

Meet June Zhang, M.D.

Dr. Zhang grew up in Seattle and received her MD degree from the Medical College of Wisconsin. She completed her pediatrics residency at Children's Hospital of Oakland in 2006 and her allergy and immunology fellowship at the Children's Hospital of Pittsburgh and University of Pittsburgh Medical Center in Pennsylvania in 2008. She started her career in private practice with Allergy, Asthma & Immunology Associates in Dallas, Texas where she also was a clinical instructor of Allergy/Immunology at the Children's Medical Center of Dallas, University of Texas Southwestern Medical Center. She loves children and has extensive training in asthma, food allergy, eczema and other allergic conditions . Dr. Zhang is Board Certified both in Pediatrics and Allergy & Immunology. She also is a member of American Academy of Allergy, Asthma and Immunology and the American College of Allergy, Asthma and Immunology.

Dr. Zhang is excited to be a part of our group and to contribute to the health and well-being of our patients. She plans to spend the remainder of her career in the Bay Area working closely with Dr. Engler as well as being nearer to her family and friends.

Dr. Zhang enjoys cooking, painting, traveling and spending time with family and friends. She is also proficient in Chinese (Mandarin).


Our Nurse Practitioners

Brooke Leon, N.P.

Brooke Leon earned her Bachelor’s degree in Health Sciences with a minor in American Sign Language from California State University East Bay in June of 1994. She then received her Bachelor’s degree in Nursing in May of 1996 and achieved her Master’s Degree in Nursing as a Family Nurse Practitioner at the University of San Francisco in May of 2000. While completing her Master’s degree, she was employed as a registered nurse at the Allergy and Asthma Clinic where she was able to work closely with our medical director, Dr. Engler. During this time, she had the opportunity to assist in the management of patients and help provide ongoing care and education to patients with acute and chronic allergic diseases. As a board certified Nurse Practitioner, she is a member of the Sigma Theta Tau Nursing Honor Society and is a frequent lecturer on the subject of allergy and asthma. She has provided a number of educational seminars to many health care professionals in the community, as well as in other cities on the West Coast.

When she is not taking care of patients, Brooke enjoys exercising, baking and cooking. She also loves to participate in outdoor activities and travel with her husband and 2 children.

Elisabeth Denker, N.P.

Elisabeth Denker earned her Bachelor’s Degree in Science and Nursing from Columbia University in New York City. She also completed her Master’s Degree in Nursing in the Family Nurse Practitioner Program at Columbia University. She achieved a Bachelor’s degree in Sociology and a Minor in Art History and Gender Studies from Santa Clara University. She is certified by the American Academy of Nurse Practitioners and she is a member of both the Sigma Theta Tau Nursing Honor Society and the Phi Beta Kappa Honor Society. When she is not taking care of patients, Elisabeth enjoys all winter and water sports, especially scuba diving. She also loves to cook and travel.