Excellence in allergy care for your children

Welcome to Proactive Allergy!

Leading evidence-based treatment

to support children living with allergies

Dr Tom Marrs


Tom read Medicine at Cambridge University before joining King’s College London to help run the EAT Study. This trial showed that dietary consumption of allergens from infancy can prevent food allergy.

Tom’s PhD assessed how eczema develops & leads to food allergy.

Dr Tom has been a Consultant for over five years at the Children’s Allergies Department within Evelina London, Guy’s & St Thomas’ Trust; the largest Paediatric Allergy Centre in Europe. He runs two services;

  • Infant Allergy Prevention Service
  • Joint Gastroenterology-Allergy Service

Tom directs the Allergy Academy from King’s College London.

Tom led the Scientific Programme Committee for the British Society of Allergy & Clinical Immunology for 3 years. He collaborates widely with Specialist Allery Societies, the Royal College of GPs, Tertiary Allergy Centres across the UK and international journals for editorial review.


The skin provides a gateway into the child’s immune system.

Skin management is of critical importance for managing allergies.

  • Eczema
  • Cradle cap
  • Atopic dermatitis
  • Contact dermatitis

Food allergies affect 1 in 12 children and have a significant impact upon quality of life. By ensuring accurate diagnosis, proportionate avoidance and planning for accidental exposures, quality of life can be hugely improved.

  • Immediate food allergies
  • Life threatening reactions (anaphylaxis)
  • Non-IgE food related responses
  • Eosinophilic oesophagitis

We live among a wide range of environmental allergens. These can trigger skin rashes, itching eyes, stuffy noses, airway and chest conditions, affecting sleep, concentration and lifestyle.

  • Hay fever
  • Perennial house dust mite allergy
  • Cat and dog allergies
  • Asthma
  • Allergic asthma

Are You Worried About Weaning?

Babies can reduce their risk of developing food allergy to a food by eating it regularly. It is best to plan your child’s assessment when starting to eat. 

Skin testing allows results in 15 minutes before leaving your consultation. Please do not give your child any antihistamine for 5 days before the appointment. Bring up to three fresh fruit or vegetable if you are worried about reacting to any of these. Only small pieces are required for skin testing; usually ‘skin on’ is best.

Blood Testing

A wide range of specialist component and microarray blood tests are available. Clinic facilities have separate fees for phlebotomy alongside the price of each blood test. 

Home blood testing is available for microarray testing, which is managed by Proactive Allergy. 

‘Desensitisation Treatment’

Pollen, dust mite and pet allergies can be ‘dampened’ by desensitisation. This treatment has a benefit within the first few months and will make hay fever and perennial rhinitis symptoms more manageable. Daily melting-wafers and drops under the tongue are effective and best results with long term dampening are achieved through three year treatment.

Finding our Face-to-Face Clinics

St Anthony’s Hospital

801 London Rd, Cheam

Worcester Park, SM3 9DW

0208 337 6691

OneWelbeck Skin & Allergy

1 Welbeck Street

Marylebone, W1G 0AR

0203 653 2007

New Malden Diagnostic Centre

Groves Med Centre, 171 Clarence Ave

New Malden, KT3 3TX

0203 277 0160

Fees and Insurance Guide

Skin Prick Testing available for face-to-face appointments alongside clinic appointment only.

Home blood testing for children at least 6 years of age after remote consultation across UK.

New Consultation Follow Up Skin Prick Test Home blood test
30 minutes
25 minutes
20 minutes
Lancets delivered for children > 5 years

Insurance Recognition Provider Numbers for Proactive Allergy

AXA Provider Number – TM02535

AVIVA Provider Number – 600142356

BUPA Provider Number – 06077957

WPA Provider Number – 921001550

Cigna Provider Number – 218318

Vitality Health – 6077957

Book by phone:

07738 630 172

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