What are allergy shots and how effective are they?

Desensitising or hyposensitising vaccines, also known as allergy shots, are vaccines that form part of the aetiological treatments (i.e. ones that target the causes) used for allergic diseases. If, for example, you are sensitised to certain environmental substances that you are forced to breathe in, you can cope with them effectively by getting vaccinated.

The only approach that does not require treatment with drugs is to avoid any exposure to the substance that is causing the allergy.

But allergic patients are well aware that far too often this strategy is difficult to put into practice, because they are forced to live with the substance or simply cannot control when it will appear.

So what alternatives are there? You could try preventive medicines, such as antihistamines, but they are not always fully effective against the symptoms. You also have to take them indefinitely (they are lifelong treatments) and sometimes they have some unwanted side effects.

On the other hand, allergen immunotherapy (aka allergy shots) is a highly effective treatment. Its progress has been spectacular over the last 100 years and, in fact, the WHO (World Health Organisation) considers it to be the only treatment capable of altering the course of the disease. Research is ongoing to develop specific vaccines for more and more types of allergies.

What types of allergies already have vaccines?

The most common allergies already have their own immunotherapy treatment. Hypersensitivity to mites, fungi, pollen, animal epithelia, latex, some foods and insect bites can be treated with allergy shots.

However, there are some other allergies that cannot yet be treated with allergen immunotherapy. Some food allergies, some types of dermatitis and allergies caused by certain drugs (e.g. penicillin) are yet to benefit from vaccines. But research is still ongoing to achieve effective results for these diseases as well.

What types of patients should receive allergy shots?

The way in which the disease manifests itself in each patient must be considered. If the symptoms are not very severe or are improving without the need for pharmacological therapy, vaccination is not necessary. It would also not be necessary if exposure to the allergen can be easily avoided.

But if you are an allergy sufferer who experiences very severe, frequent or disabling symptoms, vaccination may be highly recommended for you.

Efficacy of vaccines

Allergy vaccination will be more effective the earlier it is administered, once a correct diagnosis has been made. However, before trying this treatment, it is always advisable to wait for a certain amount of time to see how the allergy progresses. Having said that, if you wait too long and the symptoms get significantly worse, its efficacy may be reduced.

With this in mind, another reason why allergen immunotherapy may be less effective is if the patient is sensitised to multiple allergens.

You start to feel the effects of the vaccine 6 to 12 months after starting treatment, but its effectiveness peaks around the second year. The duration of immunotherapy treatment is usually 3 to 5 years, depending on the clinical judgement of the specialist.

The vaccine is administered in gradual doses, until the optimal or effective dose is reached. This is why its effects are also gradual. In the short term, the aim of vaccination is to reduce the symptoms. In the long term, it prevents the progression of the disease. Following treatment, the effect can last for many years or for a lifetime.

At Probelte Pharma we have spent over 20 years manufacturing and researching allergen immunotherapy treatments, developing vaccines that target the cause of the disease.

Probelte Pharma, advances in immunotherapy.