Question:

I have suffered from hay fever and asthma since childhood (I am now 39). Last year I was eating a plum and my mouth went itchy, my throat swelled up and I was breathless. My GP referred me to an NHS allergy clinic, where I was told that I have oral allergy syndrome (OAS). They said I will gradually become allergic to eating various fruits and nuts, and that as this happens I must stop eating them. I was also given an EpiPen to use if I have a severe reaction. I want to eat fruit but am pretty scared - it has since happened with peaches and I've started to feel 'itchy' around apples. Should I avoid the whole range of potential problem foods, or just plough on? Are there any alternative treatments that may help?

The NHS consultant
Dr Pierre duge

Oral allergy syndrome (OAS) is a tingling in the mouth, throat and sometimes lips precipitated by eating raw fruits. Your type of reaction is associated with sensitisation to silver-birch pollen, a common cause of hay fever in April and May. It used to be rare, but cases have increased over the past 20 years. That said, less than a third of people with silver-birch sensitisation will go on to develop OAS. It can involve almond or any fruit from the rose family including apple, plum and nectarine: some patients react with one fruit, some with more. It isn't usually dangerous - but you have experienced breathlessness, which is probably associated with your asthma, so it may be more severe in your case. The standard treatment is to avoid raw fruit - once it has been processed or cooked, the allergen is destroyed and it is safe to eat, so you should be fine to enjoy stewed or canned fruits.

· Dr Pierre Dugue is a consultant allergist at Guy's and St Thomas' Hospital

The alternative practitioner
Claudia Louch

There is evidence that OAS is associated with a vitamin C deficiency, as reported in the Journal of Allergy and Clinical Immunology in 2006. In a trial, an OAS patient treated with vitamin C was asymptomatic after a month. You don't need mega-dose supplements - foods such as potatoes, cabbage, citrus fruits and berries should provide the required 40mg a day. Omega-6 and omega-3 essential fatty acids may also help - these have an anti-inflammatory effect when taken together in formulations such as BioCare EPA 1000. They can be taken as daily supplements or for a period after an attack. As a phytotherapist I would also recommend plant-based remedies. Gingko biloba leaf is a great anti-inflammatory agent. Stinging nettle (a rich source of vitamin C), burdock root and marshmallow root are all good for allergies. A phytotherapist will make an exact preparation for you and a customised tincture would be used for one month after an attack.

· Claudia Louch is a clinical nutritionist, pharmacologist and phytotherapist at the Hale Clinic

The private specialist
Dr Adrian Morris

The classic pattern is that a patient develops hay fever in their teens, then slowly develops OAS in their twenties. There is an alternative treatment for silver-birch pollen hay fever called desensitisation immunotherapy, and although it is not an established treatment for OAS, clinical observation and some trials show that it can reduce symptoms in the long term. You start by taking a minute amount of the allergen by weekly injection, and over a 12-week period the dose is doubled each week so that the body becomes able to tolerate it. Follow-up doses taken monthly for at least three years build long-term immunity. Such treatment is widely used in Germany, France and Spain, and while many UK clinics now offer the treatment for venom and grass-pollen allergies, the silver-birch pollen treatment is more difficult to get here. This will change over the next few years, so you could sit it out or consult an allergy specialist in Germany, France or Spain.

· Dr Adrian Morris works at the Surrey Allergy Clinic

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