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How do I know what I'm allergic to?
Last reviewed: 03.07.2025

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Modern medicine considers allergies as a combination of several diseases that merge into a single pathological process. And this is not surprising. There are many factors that influence the development of sensitivity to an allergen - heredity, mental state, cosmetics, dust, etc. Of course, everything depends on immunity, but doctors' prognosis is not comforting - more and more people are becoming susceptible to allergic reactions.
The course of allergies varies from patient to patient. The most important thing is not to confuse, for example, an allergic reaction to food products and ordinary intolerance. Here a natural question arises: "How do I know what I'm allergic to?" First, remember what the last time the exacerbation occurred. Second, write down all the "suspected" products, substances, etc. on a piece of paper. Third, you can start checking the list yourself. Be careful, as an overdose can cause another attack in a more severe form. For some people, it is enough to imagine, add the taste, smell of a true allergen, and the first symptoms of the disease appear.
How to find out the cause of allergies?
Determining the source of an allergic reaction at home is possible through trial and error, which can result in a life-threatening condition.
Doctors have a lot of methods at their disposal on how to find out the cause of allergies in a more reliable way, without playing fortune teller. For example, skin test methods, which are divided into the following types:
- Trick testing - using an injection;
- scarification test - the allergen is applied by scratching the skin;
- intradermal test - the suspected substance is injected with a syringe.
These types of examinations are carried out by examining the skin of the forearm area after contact with a small amount of purified allergen.
How to find out what you are allergic to in the most informative way? Allergists use provocative testing. The essence of the method is to place the allergen directly into the hypersensitive organ. In the case of a primary reaction from the eyes, the provocateur is introduced into the conjunctival sac, in the case of allergic rhinitis - into the nasal sinuses, in the case of asthmatic manifestations - the allergen is inhaled using an inhaler. Such a study of the patient's condition when interacting with the source of the allergy requires the presence of a physician who can provide emergency assistance if necessary.
How do you know if you have an allergy?
Allergies manifest themselves on any skin surface, can “disguise” themselves as a runny nose, and the duration of the painful condition lasts from a couple of minutes to several days.
How to know if you have an allergy? First of all, you need to remember the signs of the disease:
- redness, burning sensation in the eyes, lacrimation;
- rashes on various areas of the skin accompanied by itching (urticaria, eczema, etc.);
- changes in stool, nausea;
- persistent, dry cough, mainly at night;
- pulmonary wheezing, suffocation;
- a feeling of a lump in the throat, irritation and itching;
- prolonged nasal congestion with clear, watery discharge;
- swelling of certain parts of the body, most often the face/eyelids;
- paroxysmal sneezing without any apparent reason;
- joint pain.
The listed phenomena are of a protracted, chronic nature, aggravated in the presence of an allergen. For example, when dust accumulates at home, the patient's painful symptoms increase. Only properly done cleaning brings long-awaited relief.
How to find out if you have an allergy with medical help? A consultation with an allergist is never superfluous. It can be very difficult to identify and even understand if you have an allergy on your own. Initially, the doctor collects data on the suspected allergic manifestations based on your words. Then a special examination is prescribed - skin testing, which helps to establish the cause of the unpleasant symptoms. If necessary, a blood/sputum test, a respiratory function test, an X-ray of the chest and sinuses are performed. After that, the doctor can draw conclusions about the presence of the disease.
How to find out what causes an allergy?
Most of us do not like to go to the hospital and try to identify the cause of the allergy on our own.
How to find out what causes allergies without leaving home? Special tests available at drugstores allow you to do this. One drop of blood is enough to get results equivalent to laboratory ones. A plus on the test strip will indicate increased sensitivity to the allergen, and a minus will appear if there is no reaction. The duration of the study of each suspected substance takes half an hour.
You can also try to eliminate contact with the suspected allergen. Move your pets, do a thorough cleaning if you notice signs of increased sensitivity to wool. If the painful symptoms decrease or disappear completely, you will have to forget about animals in the house.
Dust containing mites is a common cause of allergic reactions at any age. Regular cleaning with specialized products and an air purifier can help.
Things are more complicated with children under two years of age. The child's immune system is still developing, so laboratory diagnostic methods are ineffective, even erroneous. How can you find out what the allergy is in such a situation? If there is a sensitivity to any product, parents are advised to keep a food diary. It is important to write down each product and the baby's reaction. This way, you can avoid allergic reactions to food. If there is a painful reaction to several types of food, you should first cancel all of them, and then introduce the diet one by one, carefully observing the reaction. Such advice is also relevant in adulthood.
Even if you have found the true cause of your discomfort, still consult an immunologist. A specialist will help you choose the right treatment for your specific situation, while self-therapy can only worsen the situation and lead to chronic diseases.
How to find out what you are allergic to is an important question, but it is only the first step in a comprehensive medical intervention, including: preventive measures, reducing the strength and frequency of attacks, and immune-correcting programs.