What is food oral immunotherapy, and is it safe?

Written by: Professor Adam Fox
Published: | Updated: 06/09/2023
Edited by: Conor Lynch

Top Doctors recently had the pleasure of speaking to revered consultant adult and paediatric allergist and immunologist, Professor Adam Fox, who, here in our latest article below, tells us all about food oral immunotherapy, including what it is, the results, as well as how long the process lasts.

What is food oral immunotherapy? Who is a suitable candidate?

We start by giving the patients small amounts of food that has been causing them allergic reactions. We then slowly increase the amount of this food as a way to retrain the immune system to be a little less sensitive.

The benefit of food oral immunotherapy is that it reduces the chances of you having accidental allergic reactions. It is still possible to experience allergic reactions, but it reduces the chances of this happening.


What foods are offered?

The most common that I treat is allergy to peanuts, wheat, sesame, cashew nuts, almonds, as well as offering treatment for eggs and milk.


How long does the entire process take? How often can the dose be increased?

It is a long-term treatment. It takes a little while for the doses to be increased to get to an improved level of tolerance. To do that, the patient needs to come into the clinic and be given a small dose. As long as that is tolerated, it will then be continued at home, daily, for a minimum of two or three weeks.

Then, if all goes to plan, the patient will be given a bigger dose, again under supervision, and they’ll have that every day at home for a specific period of time. On average, the process lasts around four months.


Is food oral immunotherapy safe? How common are severe allergic reactions?

There are risks involved, as you are actually ingesting the food that you are allergic to each time you dose. Thankfully, though, it is generally very well tolerated. Having said that though, severe reactions can occur and have to be prepared for.


What results can patients expect with food oral immunotherapy?

It is not a cure for the food allergy. The patients’ immune system will become less sensitive to the food that they are allergic to, although, in younger children, there is evidence in can improve the chances of the allergy being outgrown completely.


Can food oral immunotherapy help to treat food intolerances as well?

It is meant for treating immediate-type allergic reactions. Unfortunately, it will not help with things such as food intolerance nor delayed food allergies.


What age is most appropriate for oral immunotherapy?

There is research to strongly suggest that desensitising at a younger age can have less side effects and can be more effective, allowing children to tolerate better the food they are allergic to. Research also suggests that desensitising at the earliest age possible can actually lead to the child eventually outgrowing their food allergy. Any age from nine months onwards would be suitable.



Professor Adam Fox is a highly esteemed consultant adult and paediatric allergist and immunologist who can help you and your child in relation to food immunotherapy. Contact him today to book an appointment with him via his Top Doctors profile.

By Professor Adam Fox
Allergy & immunology

Professor Adam Fox is an expert consultant adult and paediatric allergist and immunologist and one of the founding consultants of the children's allergy service at the world-renowned Guy's and St Thomas' Hospitals, home to the UK's largest paediatric allergy centre. Professor Fox is one of only a handful of UK doctors with recognised higher specialist training in paediatric allergy. His specialist interests include the management of food allergies, eczema, asthma, rhinitis (including hay fever), conjunctivitis, and drug and insect sting allergy. From 2018 to 2021, he held the position of president of the British Society for Allergy and Clinical Immunology, having become the first paediatrician to be elected into this role. Professor Fox remains a trustee of the organisation. In July 2022, he became the chair of the National Allergy Strategy Group, which involves working closely with the Department of Health and Social Care.  

Professor Fox completed his clinical training at University College London, having read Medicine and Neuroscience at Cambridge University. He went on to complete specialist training in paediatric allergy in 2006, before spending nine years as clinical lead of allergy at Guy's and St Thomas' Hospitals, London; one of Europe's largest specialist allergy services, recognised as a Centre of Excellence by both the World Allergy Organisation and GALEN (European Asthma and Allergy Network). Following three years as clinical director for specialist ambulatory medicine, he began as commercial medical director for Guy's and St Thomas' Hospitals NHS Foundation Trust. In 2021, with two of his colleagues, he established The Food Allergy Immunotherapy Centre at Great Ormond St Hospital. It was here, where Professor Fox administered the first patient outside of the US Palforzia, the first licenced food allergy desensitisation product.  

In addition to his clinical work, Professor Fox has conducted extensive research and is actively involved in cutting-edge research in allergy desensitisation, asthma prevention, and food allergy, in setting up the largest allergen desensitisation programme in the UK. He has also published extensively and is the senior author of the Milk Allergy in Primary Care guideline, which has been adopted around the world and received the Allergy UK Innovation Award in 2018. Professor Fox is a professor of paediatric allergy at King’s College London, the founding director of the KCL Allergy Academy, an advisor to the National Institute of Healthcare and Clinical Excellence (NICE), and chaired a clinical guideline development group for food allergy in children. Professor Fox has lectured internationally, been involved in the production of various documentaries, and has frequently appeared in TV and print media, notably as a regular contributor to ITV’s ‘This Morning’. 
As a result of his extensive experience and expert care, Dr Fox was included in The Times' Magazine ‘Britain's 100 Best Children's Doctors’, with the Tatler 2013 Guide listing him as one of the UK's top 250 specialists. In 2007, he was recognised as 'Paediatric Allergist of the Year' by Allergy UK. He also received the Raymond Horton-Smith award from Cambridge University for his research in 2012 and a national Clinical Excellence Award from the Department of Health in 2016 and 2020. In 2016 he was awarded the William Frankland Award from the British Society for Allergy & Clinical Immunology for his contribution to the speciality. In 2018, he earned an Excellent Patient Experience from Doctify and was one of the 29 specialists to be honoured with a ‘Top Doctors Award’ from Top Doctor, voted for by other specialists.   

Allergy London, Professor Fox’s private practice, was awarded Best Allergy Clinic in London in the Global Health & Pharma Private Healthcare Awards (2019) and Best Allergy Testing Specialists in the Private Healthcare Awards (2020). On Trustpilot, the practice has a 4.9/5 rating.  

View Profile

Overall assessment of their patients

  • Related procedures
  • Food intolerance test
    Allergy testing
    Anthropometric study
    Sun allergy
    Nasal polyps
    This website uses our own and third-party Cookies to compile information with the aim of improving our services, to show you advertising related to your preferences as well analysing your browsing habits. You can change your settings HERE.