Hay fever and desensitisation

If you’ve tried the usual antihistamine tablets, eye drops, and steroid nasal spray from your pharmacy, you may want to discuss things with your doctor. They may consider prescribing a higher dose of antihistamine or a stronger steroid nasal spray. If your wellbeing is suffering despite this and it's interfering with your work, study, and sleep, they may consider referring you to an allergy service.

This is very much dependent on what is available in your local area and each clinic will have strict criteria to follow about who they accept. There are private clinics available, which can also provide options for allergy testing and treatment.

Let's consider allergic rhinitis, so we can understand ways to counter it. Pollen is a harmless substance, but if you have a particular allergy, your immune system sees it as an invader that threatens your health, and it seeks to destroy it. Your immune system does a similar job with viruses and bacteria. Mast cells are part of this response and they release histamine, which is responsible for most of your hay fever symptoms.

With continued exposure – day after day and year after year – your immune system becomes primed to the invasion and responses can get ever-bigger. This is pollen sensitisation or hypersensitivity. Steroids nasal sprays and antihistamines aim to dampen down this response once symptoms have arrived.

Desensitisation aims to prevent this snowball of symptoms from ever starting, as it re-educates your immune system to not see pollen as an enemy. Allergy immunotherapy introduces pollen in very small amounts before the season starts. Doses are gradually built up without triggering a reaction, so you’re ready once pollen arrives in high concentrations.

You will have regular injections or a tablet that dissolves under the tongue, and it will be timed about three months ahead of your particular pollen season – tree, grass, weed, and mould pollens come at different times in the year.

It’s quite a commitment and you might need to continue this for some years, but there’s a possibility this can eventually rid you of your hay fever. It’s considered safe but allergists are careful about selecting which patients they put forward for this.

It’s effective against other environmental allergens causing allergic rhinitis, such as house dust mite or animal dander, and it’s been used for wasp and bee venom allergy. Research into immunotherapy for food allergies is underway.

Good thinking – local bees collect nectar which might have captured local pollen. Many people are convinced that eating local honey desensitises them and reduces their hay fever symptoms, but unfortunately there’s not enough scientific evidence to support this. The pollen in honey is flower pollen, which doesn’t usually cause an allergic response, compared to tree or grass pollens.

This is a steroid injection given just prior to your hay fever season. Steroids are a big sledgehammer to suppress any immune response. It’s not available on the NHS as there is a lack of evidence about its effectiveness against hay fever.

However, some people are convinced of its value at stopping or significantly reducing symptoms, and it’s available to buy from some private clinics. Steroid injections come with side effects and risks, so do make sure that you have these explained to you before agreeing to any injection.