Allergy injection: find out how specific immunotherapy works

Specific immunotherapy consists of administering injections with allergens, in increasing doses, in order to reduce the allergic person’s sensitivity to these allergens.

An allergy is an exaggerated reaction of the immune system when the body is exposed to a substance that it perceives to be a harmful agent. This is why some people are allergic to animal hair or dust mites, for example, while others are not. People who are most likely to suffer from allergies are those who have respiratory diseases such as asthma, rhinitis or sinusitis.

Thus, specific immunotherapy is a good treatment option for people with allergic diseases such as allergic rhinitis, allergic conjunctivitis, allergic asthma, allergic reactions to insect bite venom or other IgE-mediated hypersensitivity diseases.

What does specific immunotherapy consist of?

The allergy vaccine must be produced for each person individually. It can be applied as an injection or as drops under the tongue and contains increasing amounts of the allergen.

The allergens to be used in specific immunotherapy must be selected based on allergological tests, which allow a qualitative and quantitative assessment of allergies. The doctor may order tests such as the allergic skin reaction test, the blood test called REST or Immunocap to know exactly what the allergens are for that person. Find out how this test is performed.

The initial dose must be adapted to the person’s sensitivity and then the doses must be progressively increased and administered at regular intervals, until a maintenance dose is reached.

Treatment time may vary from one person to another, because the treatment is individualized. These injections are generally well tolerated and do not produce major side effects, and in some cases rash and redness of the skin may occur.

Who can have the treatment

Immunotherapy is indicated for people who suffer from exaggerated allergic reactions that can be controlled. The most suitable people to carry out this type of treatment are those with respiratory allergies such as asthma, allergic rhinitis, allergic conjunctivitis, latex allergy, food allergies or reactions to insect bites, for example.

Who should not undergo treatment

Treatment should not be carried out in people with corticosteroid-dependent asthma, severe atopic dermatitis, pregnant women, elderly people under 2 years of age and the elderly.

Furthermore, it is also not recommended for people with autoimmune diseases, serious psychological disorders, who use beta-adrenergic blockers, with non-IgE-mediated allergic disease and risk conditions for the use of epinephrine.

Possible side effects

Some of the effects that may occur during immunotherapy treatment, especially 30 minutes after receiving the injections, are erythema, swelling and itching at the injection site, sneezing, coughing, diffuse erythema, hives and difficulty breathing.