One in four of us will suffer from an allergy at some point in our lives, but fortunately only a small proportion will be life threatening. However with the number of sufferers increasing every year, it’s good to know where you can get informed advice on testing and treatment.

The most common symptoms of allergic conditions like hayfever – brought on by plant pollens – are sneezing, itchy throat, red eyes and runny nose. These can be alleviated with a simple antihistamine bought over the counter from the chemist.

However some allergies, like an intolerance to nuts or bee stings, can cause sufferers to go into anaphylactic shock, which may prove fatal without emergency medical treatment with an injection of adrenaline.

The reason for the increase in the number of allergy sufferers is unclear, although some experts believe it is associated with pollution. Others blame the fact we live in a cleaner environment, which reduces the number of germs our immune system has to deal with, causing it to overreact when it comes into contact with normally harmless substances.

A substance that triggers an allergic reaction is called an allergen and some of the most common allergens include pollen, house dust mites, mould and pets, with less common allergens including nuts, fruit and latex.  An allergy develops when the body’s immune system reacts to an allergen as though it is a threat, like an infection. It produces antibodies to fight off the allergen, in a reaction called the immune response, which can cause breathing difficulties or rashes. 

The next time a person comes into contact with the allergen, the body "remembers" the previous exposure and produces more of the antibodies. This causes the release of chemicals that lead to an allergic reaction.

If you think you have an allergy, tell your GP about the symptoms you are having, when they happen, how often they occur, and if anything seems to trigger them. You may be offered a skin prick test to identify the allergen causing your symptoms.

There are various treatments from antihistamines, to steroids or even hyposensitisation (immunotherapy) which your doctor can consider, as well as careful avoidance of the allergen that triggers the symptoms.

The most common allergies are the aforementioned pollen, house dust mites, mould, pets such as cats and dogs, wasps and bees, industrial and household chemicals, and foods such as milk, nuts (mainly peanuts) and eggs. You can also be allergic to fruit, medicines such as penicillin, metals such as nickel in jewellery, and rubber.

The type of symptoms you experience depends on what you're allergic to and how you come into contact with it. For example, you may have difficulty breathing if you inhale pollen, or get an itchy skin rash if you apply a lotion containing a chemical you're allergic to, or nausea and vomiting if you eat a food you're allergic to.

Some allergic symptoms are conditions in themselves.

• Hay fever is a runny nose, sneezing, blocked nose and itchy eyes caused by contact with pollen.
• Allergic rhinitis is similar to hay fever but occurs all year round.
• Eczema is itchy inflammation of the skin that is often linked to allergy. An eczema flare can be triggered by foods, house dust mites, pollen or pet hair.
• Urticaria is a red itchy bumpy rash that can occur as part of an allergic reaction, for example to foods, drugs and insect stings. 
• Asthma is a type of breathing problem that can be triggered by allergens such as pets, house dust mite droppings in dust, pollens and moulds.
• Allergic eye disease is also known as allergic conjunctivitis, and is where the eyes become itchy and red after contact with an allergen such as pollen or pet hair. 

Some people are more likely to develop an allergy because it runs in their family. If this is the case, you're said to be atopic or to have atopy. Boys are more likely to develop an inherited allergy than girls, as are babies who have a low birth weight.

Allergic reactions can be mild, moderate or severe. In some cases they can be life threatening. This is known as anaphylaxis. Anaphylaxis is a medical emergency and needs prompt treatment.

Signs of anaphylaxis include:

• breathing difficulties
• dizziness
• changes to your skin such as itchy skin or a raised red skin rash
• swelling of certain body parts such as your lips, hands and feet

If you suspect that somebody is experiencing the symptoms of anaphylaxis then immediately call 999 for an ambulance and tell the operator that you think the person has anaphylaxis.

If you can see a potential trigger, such as a wasp or bee sting embedded in their skin, then remove it. An adrenaline injection must be given as soon as a serious reaction is suspected. If the person is carrying an adrenaline auto-injection kit, they may be able to inject themselves or you can help them to use it.

For more information on allergies and how to manage them visit www.nhs.uk.

Allergy screening service

Given the significant rise in allergies in the UK, the National Pharmacy Association and Allergy UK have developed an accredited Allergy Screening Service in some community pharmacies. They have trained a number of pharmacists to test for allergies and it is worth asking if your local chemist offers this service. Your pharmacist can also advise and – in some cases – test for allergies.  If your symptoms are severe, or affect a child or young person, the pharmacist will refer you to your GP - in all cases with severe symptoms or involving young people, you should consult your doctor first.

Trained NPA pharmacists will start by taking details of your medical history, and if appropriate, may take an IgE blood test to identify the key allergens.  If the test proves positive, your pharmacist can advise on treatment and refer clients to Allergy UK for support.

Allergy UK offers clients a tailored information pack and access to a range of ongoing support services including factsheets, newsletters, information updates, allergy alerts, peer support and expert patient training. Visit www.allergyuk.org  for more information.

While you’re asking your pharmacist for advice about allergies, you might be surprised at the range of other services they can offer. All pharmacies can give advice on many common health problems, minor ailments and medicines. Some may also offer flu vaccinations or treatment for sexually transmitted infections as well as other services. To find out more, simply ask your pharmacist or visit www.askyourpharmacist.co.uk

Pharmacies are there to help you stay well, not just to treat you when you are sick.