How are they treated, and can they be cured?
The science behind allergies is in some ways little understood. It is true to say that allergies can be cured but it’s not entirely clear to scientists how the process works – and they can’t be cured in every case. However, there are plenty of treatments available and new discoveries in allergy research are being made all the time. As with many ailments, sometimes it is a case of trial and error to see which treatment is best for an individual, and in some cases a combination of treatments will be used.
Managing your allergy involves two steps:
- Reducing the risk of an allergic reaction by avoiding the allergen, wherever possible.
- Medical treatments to reduce symptoms including medications and immunotherapy.
Avoiding allergens requires identifying the cause of your allergy and then taking steps to reduce your exposure to the allergen. For instance, many people are allergic to dust mites. Therefore, reducing dust mites in the house may help to reduce symptoms.
However, allergic reactions will still happen. Sometimes, this will be due to accidental consumption of the allergen (e.g. peanut). With many allergens, particularly those in the air or environment, it is impossible to stop allergen exposure altogether. Hopefully, avoidance techniques can improve symptoms, but medicines are often needed (especially with eczema, atopic asthma and hay fever) to provide symptom control.
Nonetheless, in almost all cases, a combination of these two approaches will result in significant improvement in allergic symptoms.
Most people with mild allergies find that taking antihistamine tablets when exposed to allergens will help. These can be taken daily and help to reduce the symptoms of allergens, such as sneezing, a runny nose and red, swollen eyes. Antihistamine works by stopping the histamine antibody from affecting the body’s cells in the way it normally would, thereby countering the symptoms. Although taking antihistamine regularly is a good preventative measure, it deals with the symptoms of the allergy rather than working to cure it.
For more serious allergies, steroids are sometimes prescribed to tackle the symptoms. Although steroids are used to treat a variety of medical conditions, they are a good option for many allergy sufferers. This is because some steroids, called corticosteroids, are nearly identical to cortisol. Cortisol is a natural hormone produced by the adrenal gland and regulates immune response. Low doses of steroids are very safe to use, however those using steroids regularly will need to have regular check-ups.
Emollient creams are generally used for skin conditions. In simple terms, they are creams which contain water and oil to keep the skin protected from allergens and lubricated to lessen the symptoms of eczema. They also keep the skin clean and free from breakages caused by scratching, which then open up the skin to the possibility of infection. These creams can also sometimes contain a small amount of steroid, known as topical steroid application.
The use of adrenaline (epinephrine) as an emergency allergy treatment is well understood by doctors, and it has saved many lives. It is used to treat anaphylactic shock, where the sudden, high levels of histamine and other substances released during an allergic reaction cause the patient to have difficulty breathing and can also cause loss of consciousness.
Anaphylactic shock can occur immediately after contact with an allergen, or up to a few hours later. Adrenaline is a hormone produced by the body that decreases swelling associated with an allergic reaction, relieves asthma symptoms, eases breathing, tightens blood vessels and stimulates the heart.
Research has shown that the sooner adrenaline is given once an anaphylactic reaction has started, the better the health outcome for the patient. This makes rapid treatment of anaphylaxis possible, rather than having to wait for ambulances carrying the medication to arrive.
For this reason, people who are at risk of anaphylaxis are often prescribed adrenaline auto injector devices (for example, Epipen, Jext or Anapen) for use by themselves or others in an emergency. It is essential that these are always carried with the allergic individual and are available for use.
Adrenaline auto-injectors look like pens and are prescribed according to the weight of the patient. Most children will be given a junior injector, but larger children and teenagers will be prescribed the adult version. Whichever style or type of device is prescribed, the doctor prescribing it should arrange training. If the doctor does not offer this, ask for it.
Once a dose of adrenaline has been given, an ambulance needs to be called and the patient should go to hospital so that any further reaction can be treated. It may be that another dose of adrenaline is needed before they can get to the hospital, and allergy sufferers who are at danger of anaphylaxis often carry two injectors for this reason. The patient may have a late phase reaction, for which the hospital can provide further treatment.
The symptoms of some allergic conditions can increase the likelihood of localised infections. In particular, irritated skin caused by eczema can be vulnerable to infection, as can the nasal sinuses of people who suffer from hay fever or perennial rhinitis. For this reason, it is important that infections are diagnosed and treated as soon as possible.
Cromoglicate works by blocking the responses of the cells that release the histamine during an allergic reaction and can be a useful alternative to an anti-histamine in preventing allergic reactions. However, this treatment only works if taken before contact with the allergen, and it can take several weeks for the effects of the treatment to be seen. Cromoglycate is mostly used in eye drops and is most beneficial in this treatment since anti-histamines do not always offer much relief from allergic eye symptoms.
Anti-Leukotrienes Leukotrienes are chemicals released by the immune system that cause swelling and secretion, and can cause allergy symptoms to persist. Anti-leukotrienes reduce inflammation and mucus production and work in a similar way to steroids, but with fewer side effects. These drugs have often been used as add-on treatments alongside treatments for asthma and allergic rhinitis. However, they are now being used more often as a first choice in treating asthma, especially in children.
Anti-IgE Drugs The IgE antibodies are the most common cause of the immune system reacting to an allergen and initiating an allergic response. New anti-IgE drugs are being developed, which aim to take the IgE antibodies out of circulation. Several studies have been conducted using anti-IgE drugs as an add-on treatment for people with severe allergic asthma. They showed that the anti-IgE medication could allow some people to reduce, and even stop, their inhaled steroid treatments. Anti-IgE drugs are now licensed for the treatment of severe asthma in adults and children over 12 in the UK, but there is still a lot of work to be done to find their place in the treatment of allergic disease.
Calcineurin Inhibitors Calcineurin inhibitors are a new treatment, currently available as two creams – Tacrolimus and Pimecrolimus (also known as Protopic and Elidel) – for use on children over the age of two. They work by reducing the sensitivity of the immune system when the skin comes into contact with an allergen. In this way they reduce inflammation, primarily in the case of atopic eczema, and can lessen itching and relieve rashes associated with allergic skin conditions.
These creams are suitable for use on almost every part of the body, and are often used when steroids have proved unsuccessful, or are not suitable, for example, on sensitive skin around the eyes. Emollients should continue to be used as well as these creams but should not be applied within two hours of applying the cream.
Vaccinations should be avoided for a period before and after, and during, the course of this treatment.
A common side effect of these creams is a burning sensation on application, which generally settles down after a few days. These drugs are thought to be safe and extremely effective in the short-term, but their safety with long-term use has yet to be proven.