WHETHER IT Is an itchy rash, sore eyes, a bout of sneezing or an altogether more serious reaction, a staggering 15 million Brits are now battling what is being dubbed a national allergy epidemic.

And four out of ten children are also thought to suffer from various allergies, with once-rare allergies becoming more and more common, according to the latest Commons Health Select Committee report.

The latest figures now suggest that as many as one in 50 children in England - or 250,000 kids - are allergic to nuts of every kind.

And incidents of anaphylaxis - the most extreme reaction to an allergy, which can prove fatal - are now far more common, with hospital admissions increasing seven-fold over the past decade.

Muriel Simmons, chief executive of charity Allergy UK, says there are several theories why allergies are on the increase in the UK.

She added: "One is the hygiene hypothesis which says that we are living too cleanly and are killing off the good bugs as well as the bad.

"The other is the way we live now - we used to be outside more but now we sit in our snug, centrally-heated, double-glazed houses and so have more contact with allergens such as the house dust mite.

"Also we're now able to eat foods from all over the world. And whereas nature used to force us to eat by rotation, with the advent of freezers now we can eat what we want when we want."

FIVE COMMON ALLERGIES AND HOW TO TREAT THEM:

ADVERSE FOOD REACTIONS

TRIGGERS: In children, cow's milk protein, hen's egg white, wheat, soya bean, cod and peanuts may cause allergic reactions.

And in adults, watch out for nuts such as brazil, almond, hazelnut, peanut and walnut, fruits including peach, apple, strawberry and citrus fruits, vegetables such as celery, tomato, onion, garlic and parsley, and seafood such as fish, mussels, crab, prawn, shrimp and squid.

SYMPTOMS: Rash, itching, body swelling, breathing difficulties, possible localised red itchy mouth and throat, and even collapse.

TREATMENT

Skin Prick tests or RAST tests (RadioAllergoSorbent Test).

The Double Blind Placebo Controlled Food Challenge (DBPCFC).

If an allergic reaction is strongly suspected but no food can be identified, a two to four week Elimination Diet is carried out.

PERENNIAL ALLERGIC RHINITIS

TRIGGERS: House dust mite droppings, pet skin flakes (animal dander from cats, dogs, hamsters and other furry pets), and occasionally indoor mould spores.

SYMPTOMS (all year): Blocked stuffy nose, headaches and earache, constant sore throats, sleep disturbances and snoring, loss of taste and smell and poor concentration.

TREATMENT

Anti-allergy and low-dose steroid nasal sprays and eye drops.

Immunotherapy: Three-year course of injections of tiny amounts of the allergen.

SEASONAL ALLERGIC RHINITIS (Hayfever)

TRIGGERS: Pollen from trees like the silver birch, ash, oak and London plane, and grasses such as timothy, rye, cocksfoot, meadow and fescue.

SYMPTOMS: Sneezing attacks, profusely runny nose, itchy or watery eyes, an itchy throat, palate and ears, loss of concentration, and a general feeling of being unwell.

TREATMENT

Antihistamine tablets and nasal sprays.

Anti-inflammatory and anti-allergy nasal sprays and nose drops.

Desensitisation immunotherapy to grass pollen.

ASTHMA

TRIGGERS: One of the most common predisposing factors for asthma are allergies to house dust mites, mould spores, pollen and pets, and sometimes food allergies.

Asthma triggers include viral infections, cigarette smoking in the home, certain forms of exercise such as running, exposure to cold dry air, medication containing aspirin, and drinks containing sulphur dioxide.

SYMPTOMS: Tight feeling in the chest, coughing, wheezing, and shortness of breath.

TREATMENT

Bronchodilators to relax the muscles around the airways.

Mainly low-dose steroids to calm airways inflammation.

ECZEMA

(Atopic and Contact Dermatitis)

TRIGGERS: Atopic Dermatitis (dry and rough skin). Food allergy in small children, house dust mites and allergy to cats and dogs may also be responsible.

Contact Dermatitis (usually only affects adults, when the skin reacts to contact with a chemical substance). Soaps, detergents and fabric conditioners, shampoos, disinfectants and bleaches.

SYMPTOMS: Irritating patches of sore skin, which can lead to depression with low self-esteem. Sufferers are also more prone to herpes and skin infections.

TREATMENT

Atopic Dermatitis

Emollients

Steroid creams and antihistamines

Oral steroid tablets and antibiotics

Wet wrapping. Wrapping with wet bandages to help better absorption of creams

Immunomodulatory eczema creams called tacrolimus and pimecrolimus seem very effective for clearing eczema on sensitive skin such as the face and have no steroid side effects.

Contact Dermatitis

Totally avoid the substance that triggers the rash

Low-dose steroid ointments and Vaseline-based emollients

REGIONAL VARIATIONS IN CARE

The Select Committee study warns that the NHS is struggling to cope with the rising numbers of sufferers, with many patients having to turn to private healthcare for treatment.

There are only six full-time specialist NHS centres for the treatment of allergies - three in London, and the others in Cambridge, Southampton and Leicester.