Our team of food allergy specialists at New England Food Allergy Treatment Centers are committed to provide excellent, up-to-date, compassionate care for patients.

We have been serving patients in our food allergy treatment centers throughout Connecticut, Massachusetts, New England, the East Coast and those traveling from outside the United States looking for effective food allergy desensitization programs.

If you have any questions for our team of board certified physicians or professional office staff, you can check out our frequently asked questions, or feel free to contact us.

Jeffrey M. Factor M.D.
Medical Director, FAAAAI and FACAAI

Dr. Jeffrey M. Factor is clinical professor of pediatrics at the University of Connecticut School of Medicine. He is the Division Head, Allergy and Immunology, at Connecticut Children’s Medical Center and Director of its Food Allergy Clinic.

Dr. Factor is a magna cum laude graduate of Brown University where he was elected Phi Beta Kappa. He completed his pediatric residency at The Albert Einstein College of Medicine and the Montefiore Medical Center in New York. His Allergy and Immunology Fellowship training was at The New York Hospital – Cornell Medical Center in New York.
Dr. Factor is board certified in allergy and clinical immunology, and was recertified in 2001. He is a Fellow of the American Academy of Allergy, Asthma and Immunology and the American College of Allergy, Asthma and Immunology. He has written articles on food allergies, asthma, and skin testing and is active in patient education and advocacy groups. He has served on the Executive Council of the New England Society of Allergy (President 2001-2002), is a member of the Connecticut Allergy and Immunology Society, and the Connecticut Chapter of the American Thoracic Society. Dr. Factor has volunteered his time at the American Lung Association’s Camp Treasure Chest summer camp for asthmatic children in Connecticut. He helped establish a hospital asthma management program at Middlesex Hospital in Middletown, Connecticut and lectures frequently about allergic conditions, in particular, asthma and food allergies. Dr. Factor has been recognized in the Best Doctors in America, Hartford Magazine’s “Top Doctors” and Connecticut Magazine’s “Top Physicians” and “Top Docs for Women.”Dr. Factor lives in Avon, Connecticut with his wife Susan and their three daughters.
Jason O. Lee, M.D.
Physician, FAAAAI and FACAAI

Dr. Jason Lee is a Clinical Instructor in the Department of Medicine at the University of Connecticut School of Medicine. Dr. Lee is board certified in internal medicine as well as allergy and clinical immunology.


Dr. Lee holds hospital privileges at Hartford Hospital, Connecticut Children’s Medical Center, Middlesex Hospital, and Saint Francis Hospital and Medical Center. Dr. Lee earned his medical degree from the University of Medicine and Dentistry of New Jersey. Following medical school, he trained in internal medicine at Mount Sinai Medical Center in New York. Dr. Lee completed his allergy and immunology fellowship at Mount Sinai Medical Center as well. Dr. Lee is a member of the American Academy of Allergy Asthma and Immunology, the American College of Allergy Asthma and Immunology, the New England Society of Allergy, the Hartford County Medical Association, and the Connecticut Allergy Society. Dr. Lee holds special interests in asthma, food allergy, and chronic sinusitis. Dr. Lee has been recognized by the Connecticut Magazine’s “Best Doctors.”
Louis M. Mendelson, M.D.
Physician, FAAAAI and FACAAI

Clinical Professor of Pediatrics, University
of Connecticut School of Medicine. Past Executive Board Member, American
Academy of Allergy, Asthma and Immunology.


Past President of New England Society of Allergy and Connecticut State Allergy Society.
Margaret A. Vallen, M.D.
Physician, FAAAAI and FACAAI

Dr. Vallen is a magna cum laude graduate of Gettysburg College where she was elected Phi Beta Kappa.  She earned her medical degree from the Medical College of Pennsylvania, now Drexel Medical School.

She completed her residency in Internal Medicine, Chief Medical Resident year after her Internal Medicine residency, fellowships in Pulmonary and Critical Care medicine, and in Allergy and Clinical Immunology, all at the Boston University Medical Center.  She is certified by the American Board of Internal Medicine with subspecialty certification in Pulmonary and Critical Care, and she is certified by the American Board of Allergy and Immunology and was recertified in 2013.  She was elected into Alpha Omega Alpha Medical Honor Society at the end of her Chief Medical Residency.Dr. Vallen is on the staff of the South Shore Hospital.  She has previously been on staff at The Boston Medical Center and Beth Israel Deaconess Medical Center.  Dr. Vallen is a Fellow of the American Academy of Allergy, Asthma & Immunology, a Fellow of the American College of Allergy, Asthma & Immunology, and a Fellow of the College of Chest Physicians.  She is a member of the Massachusetts Medical Society, the American Thoracic Society, and the New England Society of Allergy.She is the mother of twins and resides with her husband on the South Shore, Massachusetts.  She is on the Board of South Shore SNAP-South Shore Special Needs Athletic partnership.
John A. Johnson D.O.
Physician, AAAAI and ACAAI

Dr. Johnson is a board-certified allergist and immunologist. He is an attending physician at the Allergy & Asthma Centers of Cape Cod. In addition, Dr. Johnson maintains a clinical appointment at the Cleveland Clinic Foundation serving patients in Northeast Ohio.

Dr. Johnson graduated magna cum laude with a bachelors degree from the honors program at Syracuse University. He earned his medical degree from the University of New England College of Osteopathic Medicine. After training as an internist at Saint Vincent Hospital, he attended fellowship at the Case Western Reserve University – School of Medicine.Peanut oral immunotherapy (OIT) was incorporated into his allergy fellowship, which provided over a year of experience in peanut OIT during that time. Further, Dr. Johnson was the first to diagnose green tea-induced anaphylaxis as well as pumpkin seed-induced anaphylaxis. He also diagnosed the first, laboratory confirmed case of Zika virus in the state of Massachusetts.Dr. Johnson has 17 peer reviewed publications with a majority being published in Annals of Allergy, Asthma & Immunology. He recently published a book chapter on asthma, and served as a clinical investigator in several replacement immunoglobulin studies. He has delivered 8 invited presentations to peers, including two at national conferences and an international presentation on anaphylaxis to consulates representing countries throughout the world, which was recognized with a commendation from the State of New Hampshire Governor for advancing the field of allergy & immunology.Being awarded a grant from the American Heart Association during college ignited Dr. Johnson’s passion for research. His research focused on tissue-engineered, replacement heart valves for children at Boston Children’s Hospital in collaboration with Harvard Medical School and Massachusetts Institute of Technology. His contributions were published in Circulation, the premiere cardiology research journal. Subsequently, at the University of Central Florida - College of Medicine, his research on Huntington’s Disease was published on the cover of Nature Medicine.Dr. Johnson holds memberships in the American Academy of Allergy, Asthma, and Immunology, American College of Allergy, Asthma, and Immunology, the New England Society of Allergy, American Association of Immunologists, Clinical Immunology Society, Society for Pediatric Dermatology, and American Contact Dermatitis Society.
Janina Gilo-Tomkins, APRN

Janina received her BA from the University of Pennsylvania and her MSN from Yale University.  She began her clinical practice as a Family Nurse Practitioner in 2006 and has been specializing in Allergy since 2012.

Prior to joining NEFATC in April 2015 she worked in Pediatric Allergy/Immunology at Yale, where she managed the care of patients with food allergies, allergic rhinitis, asthma, atopic dermatitis, and chronic urticaria, while overseeing patients undergoing food challenges, immunotherapy and Xolair treatment. She also has a background in primary care pediatrics and internal medicine, and is an allergy practitioner at the VA Healthcare center. Janina is a clinical preceptor and mentor for graduate students at the Yale School of Nursing.
Morgan Denno, APRN

Board Certified Family Nurse Practitioner, American Nurses Credentialing Center.  Master of Science in Nursing, Sacred Heart University.  Bachelor of Science in Nursing, Western Connecticut State University.


Affiliate with Connecticut Children's Medical Center, Department of Otolaryngology.