The symptoms of allergy result from an over-reaction to external substances. Initial contact with an allergen (such as pollen) sensitises the immune system and leads to production of immunoglobulin E (IgE) antibodies, which bind to mast cells. On re-exposure, the allergen binds to IgE on the surface of mast cells, releasing mediators such as histamine, which produce an inflammatory response.

In the case of hayfever, pollen from grass, trees or similar substances gets into the upper respiratory passages (nose, sinus, throat and eyes). Mediators released from mast cells cause an inflammatory reaction in the nasal turbinates (conchae) and frontal cavity, producing discharge and swelling, and leading to the familiar symptoms of itchiness, sneezing, congestion and nasal discharge (‘runny nose’).

Symptoms may be perennial, caused by ever-present allergens such as the house dust mite or animal dander, or seasonal, caused by allergens such as tree and grass pollen. Hayfever seasons vary from year to year depending on the weather, but generally the tree pollen season runs from January to mid-June, while the grass pollen season typically occurs from mid-March through until early October. The incidence of hayfever varies across different regions of the UK with the worst areas being inland lowlands, such as the Midlands and the rural areas of southern England. The best places for hayfever sufferers to live are coastal areas of the UK, and mountain and moorland areas, where pollen counts are lower.

Like other allergic diseases (e.g. asthma), the incidence of allergic rhinitis is rising worldwide, with possible reasons for this including changes in diet, use of antibiotics, pollution (such as cigarette smoke and car exhaust fumes) and climate change. The Met Office reports that the UK has had its 10 hottest years on record since 1995, which has had a knock-on effect on the pollen seasons. According to the National Pollen and Aerobiology Research Unit, tree pollen seasons are starting earlier and grass pollen seasons are lasting longer. For hayfever sufferers, this means there are longer periods when symptoms occur and more people are likely to have the symptoms.

What are the signs of hayfever?

Release of mediators produces immediate (early phase) symptoms, with the most common early signs of hayfever including sneezing, itchiness, nasal congestion and a clear nasal discharge. Allergic conjunctivitis (itchy and watery eyes) is also a common sign. Hayfever symptoms can sometimes appear to be similar to the symptoms of a cold1 but cold symptoms usually decrease after about five days.

Further complex processes in the mast cell produce late phase symptoms. Signs of long-term (chronic) hayfever include prolonged nasal congestion, loss of smell and increased reactivity to other irritants.

Hayfever symptoms vary in severity from person to person, and can even vary in an individual year on year, depending on weather conditions and pollen counts. Pollen counts are intrinsically linked to weather conditions, with the amount of sunshine, wind or rain affecting the count. On sunny days, when more flowers
are open, or on windy days when pollen spreads easily, more people may suffer symptoms; while on rainy days, when pollen is cleared from the air, fewer people suffer symptoms1. 

How can the pharmacist help?

Increased rates of hayfever are likely to mean more people visiting their pharmacist for advice on the condition. Recognition of allergic rhinitis symptoms in patients presenting in the pharmacy is often fairly straightforward, particularly when seasonal factors can help with the diagnosis. A pharmacist can check to see if it is likely a person has hayfever based on the symptoms and the time of year they occur. If the pharmacist thinks that someone does have hayfever, they can either recommend a suitable treatment or recommend that the patient sees their GP for further advice.

When to refer to a doctor

Hayfever symptoms are generally quite straightforward for the pharmacist to recognise and treat. However, it is best to refer to a doctor if any of the following occur:

  • Vision is affected;
  • Eyes are swollen;
  • Headache, fever or wheezing is present;
  • Forehead feels swollen;
  • There is white-yellow nasal discharge;
  • Symptoms persist for more than five days after starting treatment.

Treating hayfever – patient self-help

Although hayfever treatments available today allow sufferers to control symptoms without too many lifestyle restrictions, it is often useful to recommend simple measures to reduce exposure to the allergen. There are ways of doing this such as:

  • Check pollen forecasts and if the count is high try to avoid outdoor activities;
  • Try to keep windows and doors shut during the pollen season to prevent spores from entering the house;
  • Ensure the car is fitted with a pollen filter;
  • Wash hair frequently to remove pollen particles;
  • Avoid tasks such as mowing the lawn.

However, it is very difficult to completely avoid exposure to pollen and other allergens, particularly during the summer months when people are more likely to be spending time outside.

Medical treatments available in the pharmacy

There are several types of treatment available for hayfever including tablets, nasal sprays and eye drops.

Mast cell stabilisers e.g. sodium cromoglicate (SCG)

Nasal sprays based on SCG (e.g. Rynacrom) are not particularly effective2,3 in treating the nasal symptoms of hayfever, but SCG eye drops (e.g. Opticrom Allergy) are rapidly effective and, along with antihistamines, are a first-line treatment for allergic conjuctivitis4.

Corticosteroids

Nasal corticosteroid sprays (e.g. Nasacort) inhibit the inflammatory response and are extremely effective against all nasal symptoms but may take several days to become fully effective. As they act at several points in the allergic process, they are more effective than antihistamines at relieving nasal congestion. Corticosteroid nasal sprays available to the pharmacist all have a lower age restriction of 18 years.

Antihistamine nasal sprays

Fast-acting (within minutes), but they are more effective at relieving sneezing, itching and discharge than nasal congestion.

Oral antihistamines

Effective at relieving immediate symptoms, particularly itching, sneezing and discharge, but they are relatively ineffective on nasal congestion.

Decongestants

Decongestant nasal sprays containing sympathomimetics (e.g. xylometazoline, naphthazoline or oxymetazoline) provide quick symptomatic relief from congestion but should only be used for short periods (five days maximum) as prolonged use can lead to rebound congestion.

References

  • www.nhs.uk/conditions/hay-fever/Pages/Introduction. aspx?url=Pages/What-is-it.aspx
  • Treatment of seasonal allergic rhinitis. MeReC Bulletin 1998; 9(3): 9–12.
  • Durham SR (ed). ABC of Allergies 7th ed. Chapter 5. London: BMJ Books, 2004.
  • Durham SR (ed). ABC of Allergies 7th ed. Chapter 7. London: BMJ Books, 2004.