Believe it or not, Spring is on its way, which means that pharmacists can soon expect to see the annual increase in requests for treatment for hay fever, amongst other allergies which are related to an improvement in the weather. Despite the fact that these are conditions that we pharmacists will be particularly au fait with, it’s worthwhile having a fuller understanding of how these conditions actually work, and also to refresh our knowledge about how these common conditions should be treated.
Part of a bigger problem?
As we know, hay fever falls under the broader umbrella heading of allergy, which is one of the most widespread conditions in the UK, and includes conditions such as food allergy, anaphylaxis, and eczema, amongst others. Allergy is a big problem in the UK, with approximately 21 million people across the country being affected by at least one allergy type, with a group of around 10 million people having more than one allergy. When we delve further in the numbers and focus on hay fever, we can see that around 20% of the UK population are affected by this condition in one way or another, meaning that it’s something that will take up a lot of a healthcare professional’s time, particularly if they’re in primary care! The severity and extent of effect of these conditions is even more apparent when we take a look at the cost of allergy, including hay fever, to the NHS, with £900 million being spent annually on the primary care side, and an additional £68 million being spent on allergy-related hospital admissions(1).
It is also important to remember that whilst hay fever isn’t necessarily regarded as being a “serious” condition, it has the potential to lead to very serious outcomes in patients with particular comorbidities. For example, approximately 80% of patients who have a history of asthma also have hay fever, meaning that exposure to pollen can bring on an asthma attack(2). Which this is considered, it is clear that the management of these conditions is very important, both for the overall health of the patient, in addition to their overall quality of life.
Due to the nature of hay fever, its importance, and the exceedingly high likelihood that you will be dealing with droves of patients who are afflicted with this condition in the coming months, the remainder of this article will focus on hay fever, and provide some points, which will enhance your management of this condition.
So, what is hay fever anyway?
Hay fever, sometimes referred to as allergic rhinitis, is classically characterised by symptoms such as sneezing, runny/blocked nose, itch, and post-nasal drip, with these symptoms being brought about by the inflammation of the mucosal tissues of the nose as a result of an allergic reaction to pollen. In addition to these symptoms, hay fever can also bring about involvement of the eyes and sinuses, leading to irritation, pain, and general discomfort for the sufferer.
From a biochemical point of view, hay fever comes about due to the sensitisation of the patient to allergens, such as tree or grass pollen. During this process, allergens are processed by antigen presenting cells (such as dendritic cells, which are present on the surface of the nasal mucosa), which then present selected peptides from the allergens on major histocompatibility complex class II molecules, with these molecules going on to bring about a chemical cascade involving a number of immune cells, such as naïve CD4+ T-cells and specific Th2 cells. The resultant chemicals then lead to further immune cell activity, bringing about the production of specific IgE, and proliferation of cells such as eosinophils, mast cells and neutrophils(3).
Of course, some of these processes take time, with others occurring much more quickly after subsequent exposure to the trigger allergen, which is why the presence of both an “early” and “late” reaction is characteristic of hay fever in most patients. In the early stage, sneezing and rhinorrhoea can develop within 30 minutes of exposure, with the late stage taking place around 6 hours after exposure, leading to nasal blockage, which can then take time to subside. The nature of these outcomes and the time factors related to each one indicate that a range of treatments can be required for these conditions, and that it may be suitable to recommend a combination of treatments to your patients that can provide both immediate relief, as well as a long-term reduction of their hay fever symptoms.
Treatment strategies for hay fever
You will be aware that the range of products available for hay fever is large and that the potential market for these products in your pharmacy is huge due to the number of sufferers and because of the duration of time that the condition can persist. However, it’s prudent to be thoughtful when recommending products to your patients – a quick web search will return many stories of disgruntled patients who have been recommended costly products which are deemed “identical” to much cheaper products which are also available over the counter, for example. As a result, it is a good idea to make sure that you reinforce the reasoning behind your recommendation of products, as this is more likely to keep your patients both happy and informed, leading to improved outcomes.
In general, hay fever should be managed using a stepwise approach, which is based on the information that you glean from your patient with regard to both the severity and duration of their symptoms. As always, appropriate questioning about these factors, in addition to the ability of the patient to comply, the safety profile of the medication, and the cost-effectiveness of the selected product(s) are all-vital in bringing about effective condition management.
Antihistamines
As suggested by their name, antihistamines function by reducing the production of histamine, which is produced by stimulated mast cells during the early response phase of the allergic reaction. This suggests that the use of these medications is suitable for the immediate treatment of the condition, bringing about alleviation of the initial symptoms, but not having an effect on long-term inflammation.
In terms of the products available, there are two main categories of molecule, namely first and second-generation. First-generation antihistamines (e.g. diphenhydramine, chlorpheniramine) have been used for over half a century, and have the classical side effects of sedation, memory impairment and psychomotor dysfunction. It is also worth noting that these particular drugs can cause a number of issues if the patient has other comorbidities, so this should always be considered. The newer, second-generation molecules (incl. cetirizine, loratadine) are structured in such a way that they exhibit a significantly smaller degree of penetration of the blood-brain barrier, and thus, do not bring about the CNS effects of their first generation cousins. As a result, guidance documents such as NICE Clinical Knowledge Summaries (CKS) recommend the use of the second-generation drugs as first line medications in situations where the use of an antihistamine is recommended.
This leads on the question of when an antihistamine is the most appropriate treatment strategy. According to the CKS, these products should be recommended first-line if the patient needs an “as-required” treatment for occasional symptoms. In situations where the patient exhibits conjunctivitis as the main symptom, is aged between 2 and 5, or if the patient prefers and oral dosage form, oral products such as cetirizine or loratadine should be recommended. In all other situations where as-required treatment is the best approach, NICE recommends intranasal azelastine – however, this is currently a prescription-only preparation, and thus would require the patient to be referred on in situations where its use is suitable.
There are other situations where the use of oral antihistamine is recommended as first line, including for those who have a predominant symptom of sneezing or nasal discharge with associated eye involvement, prefer oral products, and require preventative treatment or control over symptoms, which are frequent or persistent. Additionally, oral antihistamines are recommended where a patient is awaiting the effect of a preventative treatment to take hold, provided that they are already using an intranasal corticosteroid(4).
Intranasal corticosteroids
Another product type that is instrumental in the treatment of hay fever are intranasal corticosteroids. Their mechanism of action is known to be complex, but is not fully understood – there’s the potential that these drugs penetrate the nasal mucosa and act on the target immune cells in the locality of the nose, without exerting a systemic effect, which is beneficial, and it’s also suggested that these drugs may inhibit IgE-dependent release of histamine(5). Overall, these drugs work well to reduce the nasal effects of hay fever, and bring the patient relief.
So, when should they be recommended? If we revert to the NICE CKS document, we can see that these products should be given if the patient has sneezing or nasal discharge as a predominant symptom, and wants a preventative treatment for their persistent symptoms. Due to the nature of these drugs, they should not be recommended for “as-required” treatment, as they will not bring about a speedy effect, and are targeted for longer-term use. When it comes to the recommendation of intranasal corticosteroids, it is also important that you correctly counsel the patient on how to use the product correctly, as the drug will be in the form of a drop, or more commonly, a spray, which the patient will not be familiar with – the correct use of these products is essential to their success.
A combination approach
As mentioned above, the treatment of hay fever should be stepwise in manner, and as such, the likes of oral antihistamines and intranasal antihistamines can be combined if deemed appropriate. For example, this strategy can be combined if the patient is unresponsive to a intranasal corticosteroid, or if this can be justified by the combination of symptoms that the patient is affected by. For example, if the patient is strongly affected by sneezing, nasal congestion and allergic conjunctivitis, there may be a case for the recommendation of both products.
Other products
Of course, there are other products on the market for the treatment of the various symptoms of hay fever. One obvious omission from above is that of sodium cromoglicate eye drops. This particular preparation, which functions by stabilisation of the mast cells, reducing the inflammatory response, is indicated for symptoms of conjunctivitis brought about by hay fever, and may be a suitable additional product, should these issues persist when another treatment is used. These drops can also be a suitable alternative product, should first line treatments such as oral antihistamines not be suitable for your patient.
Avoidance of allergens
We are at an advantage when it comes to hay fever, in that we have a good idea about what causes the condition, and that advantage is even greater because the causative is environmental. This all adds up to the fact that advising your patients about allergen avoidance is a critical piece of patient counselling, and if done well, should go great lengths to reducing their symptoms, and improving their quality of life. Another benefit is that for the most part, these steps are not particularly complicated. For example, if your patient possesses an allergy to grass pollen, you should advise to:
- Avoid walking in grassy spaces during times when pollen counts are at their highest (early morning, late evening, and night time)
- Keeping windows in cars and rooms closed
- Changing car pollen filters regularly, and in line with manufacturer’s recommendations
- Check pollen forecasts regularly, and carry out the steps above at any point when pollen counts are elevated
As such, this advice should always be given to patients who you supply with treatment for hay fever.
A problem with easy solutions
Overall, hay fever is a condition that can have a massive impact on a patient’s life, but in most cases, can be easily and very effectively treated. It is critical that we offer the full service to patients suffering from the condition – the right medications (or combination of medications, tailored to the patient’s symptom profile), and advice can get a patient to a point where their hay fever becomes outdated. Knowledge of these areas and how to use our knowledge to structure a management plan for the patient will guarantee satisfaction, and importantly return custom, ensuring that your expertise remains as profitable as always!
References
(1) Allergy UK. Allergy Statistics. 2015; Available at: https://www.allergyuk.org/allergy-statistics/allergy-statistics. Accessed 03/08, 2016.
(2) Asthma UK. Hay fever treatments. 2015; Available at: https://www.asthma.org.uk/advice/inhalers-medicines-treatments/other/hay-fever/?gclid=CP2VwY_hsMsCFUko0wodppoFNw&gclid=CP2VwY_hsMsCFUko0wodppoFNw. Accessed 03/08, 2016.
(3) Min Y. The pathophysiology, diagnosis and treatment of allergic rhinitis. Allergy, asthma & immunology research 2010;2(2):65-76.
(5) Mygind N, Nielsen LP, Hoffmann H, Shukla A, Blumberga G, Dahl R, et al. Mode of action of intranasal corticosteroids. J Allergy Clin Immunol 2001;108(1):S16-S25.