With the prevalence of allergies on the rise, Holly Shaw gives pharmacists the rundown on what they need to know to advise patients

Key points

  • Roughly 21 million people in the UK suffer from at least one allergy
  • Pharmacists should play a key role in spotting allergies in patients and helping them to manage or treat symptoms
  • Infants who present with eczema are more likely to develop a food allergy in later life

 

Allergic disease is increasing, with the UK having one of the highest rates of allergy in the western world. It is estimated that 21 million people in the country have at least one allergy.1 Community pharmacists have an important role to play in the advice and information they can provide.

For many patients, the pharmacy may be the first point of contact for several reasons, including the convenience of expert knowledge without the need to make an appointment or take time off work or school. Patients are looking for advice and the appropriate treatments that are flexible and fit in with their busy lifestyles.

Pharmacists are well placed to help address the needs of allergic patients on a case-by-case basis, depending on the individual and the type of allergic condition they have. This includes:

  • Advice on the supply of OTC and PO medication.
  • Medication reviews.
  • Device technique education.
  • Education on recognising allergic symptoms.
  • Advice on allergen avoidance or reduction.
  • Signposting to another health professional or to reputable sources for allergy testing.

An overview of allergies

Allergy is an umbrella term for a group of allergic conditions, including:

  • Asthma.
  • Eczema (atopic dermatitis).
  • Hay fever (allergic rhinitis).
  • Food allergy.
  • Drug allergy.
  • Venom allergy.

It is common for allergic conditions to co-exist and research has shown that there are close links between food allergies, asthma, hay fever and eczema.2 A genetic tendency to develop allergies is termed ‘atopy’. Children with an immediate family history of allergies are at an increased likelihood of developing one, but not necessarily the same type as their family member.

The progression of allergic disease from birth to late childhood has been historically described as the ‘allergic march’, meaning the natural order by which allergic disease develops over time. The first signs of an allergic disease seen in infants are usually a food allergy and eczema, with asthma and hay fever having a later onset.

Where a food allergy and asthma co-exist, there is an increased risk of a severe allergic reaction – especially when the food allergy is caused by peanuts. Dispensing asthma and allergy medications provides a chance to review medication compliance and ensure patients know how to use their devices, such as inhalers and adrenaline autoinjectors.

Eczema

There is well-documented evidence on the link between eczema that presents in infants in their first few months and an increased risk of developing a food allergy.3 Eczema skin is dry skin and replacing water loss is very important. Emollients are the cornerstone of daily management. If parents present to the pharmacy with infants or children whose eczema appears not to be well managed, then emollient therapy is important to maintain skin protection.

Pharmacists are well placed to give advice. These come in a variety of preparations, including lotions, creams and ointments, and  all should be matched to the severity of the eczema and dryness of the skin. Pump-style dispensers reduce the likelihood of an infection as pots and tubs may become contaminated. It’s important to educate patients about the quantity, frequency and application method of each treatment.

Parents commonly have concerns over steroids. This should be addressed so that eczema flares can be appropriately treated with a steroid potency matched to the severity and location. If eczema appears to be infected (with crusting, weeping or signs of a high temperature), signpost to the GP for further management.

Hay fever

Hay fever (allergic rhinitis) is a common allergic condition affecting children and adults. A large proportion of the symptoms will be experienced during the summer because of grass pollen. It is also possible to have allergic symptoms to trees and weeds that pollinate at different times of the year.

Community pharmacists are well placed with their product and knowledge to recommend specific treatments for hay fever. Antihistamines are commonly used to treat mild symptoms, such as runny or congested nose, sneezing, and itching or watery eyes. These should always be non-sedating so they do not impact on an individual’s ability to carry out their day-to-day activities. Patient education should always be provided for correct use of nasal sprays and eye drops.

Some simple advice on pollen avoidance:

  • Wear wraparound sunglasses and a wide-brimmed hat (reduces pollen exposure to the face and eyes).
  • Monitor the pollen count and plan your day to avoid being outdoors at peak pollen times.
  • Keep windows and doors closed at home, in the office or car, to stop pollen coming inside.
  • Avoid drying washing outside as pollen can brought inside on garments, bed linen, sheets.
  • Wash or shower if you have been outside to remove pollen from the skin and hair.

Food allergy: common misconceptions

Adverse reactions to foods present in many forms, and a food allergy and intolerance are commonly confused. Adverse reactions that are not allergic include intolerances such as gluten or lactose intolerance.

There are many reasons why a particular food may cause unpleasant symptoms, such as indigestion, overindulgence and poisoning from contamination with bacteria or toxins. A food allergy occurs when the immune system mistakenly identifies an allergen as harmful and, as a result, it produces IgE antibodies as a defence mechanism.

It is not uncommon for those who experience an adverse reaction to food to request a test to confirm whether it is an allergy. Testing is not always required or appropriate, and a more detailed allergy history is required to determine the most appropriate diagnostic pathway. It is also important that those with suspected allergy are signposted to reputable allergy testing services, which will usually be via their GP.

Most food allergies are caused by a small number of foods, including:

  • Cow’s milk.
  • Egg.
  • Fish.
  • Peanut.
  • Soya.
  • Tree nut.
  • Shellfish.
  • Sesame.
  • Wheat.

Cow’s milk and eggs are common causes of allergies in children and are often outgrown by around five years of age. An allergy to peanuts, tree nuts, shellfish and fish tends to be more persistent and the likelihood of growing out of these is reduced. It is also possible to develop an allergy to a food that has been eaten before and, in rarer cases, has been in an individual’s diet for many years. The reasons for this are not fully understood.

Recognising symptoms 

Key features of IgE-mediated food allergy:

  • Symptoms occur quickly after the food is consumed.
  • Symptoms affect multiple systems including cutaneous, gastrointestinal, respiratory and cardiovascular.
  • Patients can have a severe reaction, such as anaphylaxis, which can be life-threatening.

Key features of non-IgE-mediated food allergy:

  • Symptoms are delayed in onset, often seen several hours to days after the food is eaten.
  • Symptoms mainly affect the gastrointestinal system.
  • Delayed allergies do not cause anaphylaxis.

Allergic reactions can be mild, moderate or severe. Symptoms of an allergic reaction are summarised below:

Mild to moderate symptoms of an allergic reaction include:

  • Itchy mouth, tongue or throat.
  • Swelling of the lips, eyes or face.
  • Red raised rash (hives or urticaria).
  • Vomiting, nausea, abdominal pain and diarrhoea.

Severe symptoms (anaphylaxis) of an allergic reaction are:

  • Swelling of the tongue or throat.
  • Difficulty in swallowing or talking.
  • Change in voice (hoarse voice or cry).
  • Difficult or noisy breathing.
  • Whistling noise due to narrow airway.
  • Persistent cough.
  • Dizziness or collapse.
  • Pale, floppy or sudden sleepiness (in babies and small children).

Diagnosing food allergy

If a patient presents to the pharmacist with concerns about a food allergy, and if they have no current symptoms requiring immediate attention, they should be signposted to their GP for further advice and management. The GP should take an allergy-focused clinical history, as recommended in the NICE Quality Standard (118)4 for the assessment and diagnosis of food allergy. Depending on the type of allergy suspected, they may then be referred to secondary care or to a specialist service for further investigation and testing if these options are not available in primary care.

Fact sheets on all types of allergy are available to download from the Allergy UK website at www.allergyuk.org.

Holly Shaw is Allergy UK’s nurse adviser

References

1 Mintel, (2010) – Allergy statistics- 21 million adults suffer from at least one allergy. Accessed on the 01/03/2018- https://www.allergyuk.org/allergy-statistics/allergy-statistics

2 Wang, J (2010) Management of the Patient with Multiple Food Allergies.” Current allergy and asthma reports 10, 4,pp.271–277

3 Keller MM, Dunn-Galvin A, Gray C et al (2016). Skin barrier Impairment at birth predicts food allergy at 2 years of age. Journal of Allergy and Clinical Immunology. 137, 4, pp.1111-1116.

4 NICE (2016) Quality Standard (Q118) Food Allergy. National Institute for Health and Care Excellence https://www.nice.org.uk (Accessed on the 01/03/2018)