Enzyme Potentiated Desensitisation

Jennifer Worth describes the EPD treatment that she has found so successful in combating her eczema and food intolerances.

Although many allergic people have heard of Enzyme Potentiated Desensitisation (EPD) very few know what it is or how it works.

Allergic people have a weak immune system and a low tolerance of allergens. To avoid all the allergens in the environment is impossible, so the only way to minimise the allergic reaction is to reduce the sensitivity to allergens. This is where EPD is effective. It is not a drug, it is a vaccine (with an impressive safety record), which builds up the body’s resistance over a period of time.

Most great discoveries are made by chance and EPD is no exception. In the 1960s, at St Mary’s Hospital Medicinal School in London, Dr L E McEwen was a member of an allergy research team. He observed, by chance that when a minute dose of an allergen is combined with the enzyme beta-glucuronidase, the combination will potentiate, or induce desensitisation. Thus the tongue twisting name! EPD has been extensively refined during the last 35 years and is now used in many countries.

But what is an enzyme?

The official definition is 'a specialised protein molecule that acts as a catalyst for the biochemical reactions that occur in living cells' - in other words an enzyme is an enabler. The enzyme beta-glucuronidase is present in all parts of the body and is released into the tissues during an allergic reaction. EPD exploits this natural phenomenon by combining a minute dose of beta-glucuronidase with a minute dose of allergens.

The combination produces an effective desensitisation technique which has now been adapted to give an efficient treatment for asthma, hay fever, chronic rhinitis, eczema and urticaria, IBS, ulcerative colitis and Crohn’s Disease, aching limbs and some forms of rheumatoid arthritis, migraine, headaches, memory loss, chronic fatigue syndrome and ME, childhood hyperactivity and some cases of autism. EPD is particularly effective for hay fever and eczema


I have said that minute doses of vaccine are used. This is important. EPD is an extremely low dose method of desensitising. The actual amount of beta-glucuronidase is less than that found in 1cc of blood from the average person; the amount of allergen injected is less than that used for a standard pinprick test. The dose of allergen does not increase with the treatment.

Such a minute dose means that up to 70 allergens can be included in each treatment: foods, food additives, dust mites, tobacco, pollens, grasses, moulds, gut micro-organisms and some chemicals. Dealing with so many allergens at once means that the total allergy load will be treated. Therefore the patient will not need to be tested for specific sensitivities. Many allergens cross react with each other, and most atopic people are allergic to more allergens than they think. It follows that when EPD is used, allergens will be cross-desensitised in groups and unsuspected allergies will be treated.

Atopic people also tend to develop new allergies all the time. This can be maddening as just when you think you have cracked one problem another rears its ugly head. There is good evidence to suggest that, because of the wide range of allergens used, EPD protects against this problem.

Most allergens are absorbed by inhalation ingestion or contact so EPD vaccinates for:                        
1. Inhaled and contact allergens (IC Mix - plus house dust and other mites, dust and mould spores, grasses and pollens, animal fur and dander, respiratory tract micro organisms). 

2. Food, drink and food additives allergens (food Mix - the IC mix plus a wide range of common foods and drinks, gut micro-organisms and many commonly used food additives)

3. Special vaccine for rare allergies (special mix - both of the above plus rare allergies such as building dust, algae or rare moulds, fungi, mosquito and some insect bites (not wasp or bee stings) some volatile chemicals and some type of latex)

EPD is only effective when specific allergen can be identified and isolated. Because of the number of potential chemicals allergens EPD is not helpful for those with multiple chemical sensitivity, nor is it able to address latex or drug allergies. However by stretching the immune system overall, even allergic reactions to substances not specifically covered may be improved.

Before and after

EPD has to be administered over a period of time as several months must elapse between each dose. The number of doses will depend on the age of the patient and severity of the condition. Most atopic adults will need three to five years to be effectively desensitised children respond much faster.

Preparations before, and precautions after each dose of EPD vaccine are vital. Exposure to allergens must as far as possible be avoided for one week before and three weeks after the vaccine. Each dose will affect the subtlest part of the body’s chemistry and immune system if the body is bombarded with high exposure to allergens just before or after the EPD dose the system will react violently.

For example, in my second year of treatment, I had a dose of EPD in May, the time of the year gardeners spray their roses. A few days after the treatment, without thinking, I sprayed my roses. A few days later my skin, which had been perfect for about three years, broke down completely all over my body, in some part cracking and weeping, and the itching nearly drove me mad again. It took six months to clear up.

Food allergy is common among atopic people. You will be put onto a strict diet after an EPD dose and this diet must be followed scrupulously. A strict anti-allergic diet can be the hardest part of all, especially for children or teenagers who are growing and hungry all the time. A mixed diet, consisting of many foods at each meal, is the best.

A surprisingly large number of people have a fungal misbalance of gut micro-organisms (usually called candida), which must be treated before EPD dose is given; an anti-fungal will be prescribed.

Many drugs and proprietary medicines must be avoided before and after EPD as well as perfumes hairdressing salons. Air fresheners, lavatory cleaners and chemical perfumes/odours of all kinds, deodorants, after shave, dust, animals, tobacco smoke, damp buildings and mould, new paintwork, petrol fumes-and many other things. From this recital it might seem that you should go and live on a raft in the middle of the sea. But it is not that bad. Most allergic people already have to avoid many allergens so the additional ones are not going to be a great hardship for a few weeks. The main thing is to understand that while you immune system is responding to EPD contact with all suspected allergens must be avoided.

The treatment itself

Treatment is given by injection or by cupping. The skin of the arm or leg is scratched to remove the outer epithelia and the scratched area is covered with a small cup. The EPD is injected into the cup and left to be absorbed slowly into the body, through the scratched area of the skin. The advantage of cupping is that if an adverse reaction occurs, the cup can immediately be pulled off and absorption of the vaccine will be discontinued.

Treatment is at intervals of eight and twelve weeks, three and six month progressively. EPD is a highly individualised form of treatment - nothing can be standardised - and for this reason it has only been given as Special Licence by the Medicines Control Agency on a named patient basis. The vaccine is only available to a registered allergy specialist and who has undergone special training in the administration of EPD.

My own experience

On a personal note 8 years ago I was covered in eczema from head to foot. My skin was cracking and weeping all over my body and the itching nearly drove me mad. I discovered by accident, that it was caused by a food allergy and strict elimination diet cured the eczema, but I was left with hardly anything to eat. Professor Jonathan Brostoff referred me to Dr McEwen. I have now had 5 years EPD treatment and can eat everything with no return of the dreaded eczema. Also I am far less hesitative to dust, pollen, grass, moulds, pets and so on.  

Where is EPD available and how much does it cost?

Although EPD is available on the NHS because of the dearth of allergy specialists, let alone specialists trained in EPD, you will needs to find a clinic which can offer EPD – and to get referral from your GP who will probably never even have heard of it. If you cannot wait you can go privately; some health insurance schemes will even pay for EPD treatment.  A list of private and complementary EPD practitioners is available from Action Against Allergy from The McEwen Laboratories (0118 984 1288) and from the British Society for Ecological Medicine

The Centre for the Study of Complementary Medicine in Southampton also offers EPD treatment including preliminary consultations and nutritional support. Costs vary enormously depending on what is required.

First published in 2002

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