Pre-Seasonal vs. Continuous Immunotherapy for Hayfever

Grass pollen allergy, commonly known as hay fever or allergic rhinitis, affects millions of individuals globally. It is worst during the high grass pollen count months of May to July. However, it can occasionally last well into September, depending on the particular weather. Locally, in the UK, you should expect your symptoms to go away by the second week of September in most cases.

Although downright irritative if you suffer from hayfever, the pollination of grass is an essential part of our ecosystem. Grass pollination is vital in plant reproduction, ensuring the survival and propagation of numerous grass species that form the foundation of many ecosystems and forms of wildlife.

The pollen grains can travel long distances and, when inhaled by sensitised individuals, they provoke an immune response leading to symptoms such as sneezing, itchy and watery eyes, nasal congestion, and runny nose. These can vary from very mild to severe. It can even lead to asthma exacerbation in the case of allergic asthma.

The impact of hayfever on quality of life

The impact of hayfever symptoms extends beyond physical discomfort. Grass pollen allergy can significantly affect daily activities, sleep quality, and overall well-being. People with severe hayfever often find it challenging to participate in outdoor activities during peak pollen days, which can affect their social lives and mental health.

Additionally, the constant need for symptom management can lead to frustration and fatigue.

Suffering from hayfever and studying or taking an important exam can also greatly impact your performance.

Traditional Treatments vs. Immunotherapy

Traditional treatments for grass pollen allergy primarily focus on alleviating symptoms. These treatments include:

Antihistamines: Medications that block the action of histamine, a chemical released during allergic reactions. Common antihistamines come in tablet or syrup form. These include cetirizine, loratadine, and fexofenadine. There are also antihistamines that can be administered directly as a nasal spray or eye drops.

Nasal Corticosteroids: Sprays that reduce inflammation in the nasal passages, such as fluticasone and budesonide. Some are over the counter, while the more potent steroid sprays need to be prescribed by a doctor.

Decongestants: Medications that relieve nasal congestion, such as pseudoephedrine. However, these should not be used for more than 5 days at a time, or they can have the reverse effect of worsening your nasal congestion.

Eye Drops: Antihistamine or anti-inflammatory drops to alleviate itchy and watery eyes.

Combination Treatments: If the simple treatments have failed, an allergist or even your GP can prescribe combination treatments such as Dymista which is a nasal spray containing both an antihistamine and corticosteroid. This has been shown to work well in the more severe allergic rhinitis symptoms.

Montelukast: If you suffer from asthma triggered or worsened by hayfever or other allergens, Montelukast is an MHRA approved treatment option to relieve your allergic rhinitis from 15 years old onwards.

While these treatments can be effective in managing symptoms, they do not address the underlying cause of the allergy. As a result, symptoms reappear whenever the individual is exposed to grass pollen, necessitating continuous medication use during the pollen season.

Immunotherapy: This offers a long term solution. By gradually exposing the immune system to increasing amounts of the allergen, immunotherapy aims to build tolerance and reduce the severity of allergic reactions over time. This approach can provide lasting relief and potentially lead to remission of the allergy.

Immunotherapy can be administered through subcutaneous injections (SCIT) or sublingual tablets or drops (SLIT). Both methods have been shown to be effective. They do however require an initial three year time commitment and adherence to the treatment schedule.

How Immunotherapy Works

Immunotherapy for hayfever works by gradually increasing the patient’s exposure to the allergen. This exposure occurs in a controlled environment. Unlike immunotherapy for peanuts or other allergens, immunotherapy for hayfever does not require a gradual increase in the allergen dose.

The ultimate goal of immunotherapy is to modify the immune system’s response to the allergen, reducing the severity of allergic reactions or eliminating them altogether. By doing so, patients can experience significant improvements in their quality of life and a reduction in the need for other allergy medications.

SCIT vs SLIT

Although SCIT (Subucutaneous immunotherapy) is an option for hayfever, we only use sublingual medication (SLIT) in our clinic. This is a much more convenient and non invasive way of administering immunotherapy.

Effectiveness of Immunotherapy

Both SCIT and SLIT have been shown to provide significant benefits for patients with grass pollen allergy. Studies have demonstrated that immunotherapy can:

•  Reduce the severity of symptoms by 30-50%.
• Decrease the need for symptomatic medications.
• Improve overall quality of life.
• Provide sustained relief even after the treatment has ended.

There are currently two options for immunotherapy or hayfever, pre-seasonal or continuous.

Pre-seasonal immunotherapy vs Continuous immunotherapy

Pre-seasonal immunotherapy

Pre-seasonal immunotherapy is a reasonable approach to managing grass pollen allergy by initiating treatment before the pollen season begins and continuing through it. The total duration is about 6-9 months per year.

The goal is to prepare the immune system to handle the impending pollen exposure, thereby reducing the severity of allergic reactions during the peak season. Typically, treatment starts a few months before the anticipated pollen season, often in late winter or early spring, and continues throughout the pollen period.

A typical schedule for pre-seasonal immunotherapy would be to start in December and continue until end of August.

Study Results and Statistics

Several studies have demonstrated the efficacy of pre-seasonal immunotherapy:

Symptom Reduction: Research indicates a 30-40% reduction in allergy symptoms during the pollen season for patients undergoing pre-seasonal immunotherapy for grass pollen. (source)

Medication Use: Studies have shown a 35-40% decrease in the need for additional medications to manage symptoms. (source)

Advantages and Disadvantages

Advantages:

• Pre-seasonal treatment is convenient for patients who prefer not to undergo year-round therapy. It is particularly suitable for those who experience significant symptoms only during peak pollen season.
• Cheaper option as you only have to cover the cost of immunotherapy for 9 months instead of 12 months.

Disadvantages:

• Strict adherence to the treatment schedule is necessary for optimal effectiveness. Missing doses or not starting the treatment early enough before the pollen season can reduce its benefits.
• Better effectiveness rates could be achieved if immunotherapy treatment is taken all year round for the first 3 years, as we will see in the next section.

Continuous immunotherapy (also known as Perennial Immunotherapy_

Continuous immunotherapy is where you would receiving daily doses of the allergen throughout the entire year, irrespective of the pollen season. This approach aims to maintain consistent exposure to pollen, helping to build and sustain a better immune tolerance over a prolonged period.

Continuous immunotherapy operates on the principle of consistent and prolonged exposure to the allergen. The regular administration of allergen doses helps to modulate the immune system, leading to:

Increased Regulatory T Cells: These cells play a crucial role in maintaining immune tolerance and reducing allergic responses.

Reduced Allergen-Specific IgE Levels: Continuous exposure decreases the levels of IgE antibodies, which are responsible for triggering allergic reactions.

Increased Allergen-Specific IgG4 Levels: IgG4 antibodies help to block allergens from binding to IgE, thereby mitigating allergic responses.

By maintaining these immune modifications year-round, continuous immunotherapy aims to provide sustained relief from allergy symptoms and reduce the likelihood of relapse after treatment ends.

Study Results and Statistics

Symptom Reduction: Research shows a slightly better symptoms reduction of 40-50%. The more severe your hayfever symptoms, the more of a difference you will notice with taking immunotherapy continuously throughout the year. (source)

Medication Use: Continuous immunotherapy can also lead to a 40-50% decrease in the need for additional allergy medications. This compares favourably to pre-seasonal immunotherapy which has less efficacy. (source)

Advantages and Disadvantages

Advantages:

• Continuous treatment provides a consistent exposure to the allergen, leading to the highest efficacy in reducing symptoms and maintaining long-term benefits. This approach is particularly effective for patients with severe allergies or those who do not respond adequately to seasonal treatments.

Disadvantages:

• The requirement for year-round treatment can be challenging for some patients. It demands a significant commitment and adherence to the treatment regimen, which may affect compliance.
• It is also more pricey than only taking the immunotherapy medication for 9 months a year under a pre-seasonal regime. Our immunotherapy pricing is valid for continuous therapy only as we are convinced this is the best and most effective of improving your pollen allergy symptoms.

Summary Table: Pre-seasonal vs. Continuous Immunotherapy

In conclusion, both pre-seasonal and continuous (perennial) immunotherapy offer effective solutions for managing your grass pollen allergy. There are pros and cons for each.

Pre-seasonal treatment is ideal for those with seasonal symptoms who prefer a shorter therapy duration, while continuous treatment offers more consistent and long-term relief.

If you would like to discuss the best hayfever immunotherapy options for you. please get in touch to book a consultation with Dr Salagean, our consultant allergic.