Final answer:
Having an allergy to neomycin is a contraindication for receiving the varicella vaccine to prevent the risk of severe allergic reactions. Allergy medications are stopped before allergy testing for accurate results, and immediate hypersensitivity is the classification for pollen allergies. Treatments for allergies range from antihistamines for mild symptoms to immunotherapy for long-term desensitization.
Step-by-step explanation:
When a person has a known allergy to neomycin, it is a contraindication for receiving the varicella vaccine. The presence of an allergy means that the immune system reacts to a harmless substance (like neomycin) and can cause severe adverse reactions. Since vaccines, such as the one for varicella, are designed to stimulate an immune response, introducing a substance to which a person is allergic could be dangerous and potentially lead to a condition such as anaphylaxis, a severe systemic allergic reaction. This is why a neomycin allergy is a contraindication - to prevent severe allergic reactions.
For people with allergies, commonly experienced symptoms include watery, itchy eyes, swollen tissues, and sneezing. Patients need to stop taking allergy medications before allergy testing to ensure accurate results; if one were to take allergy medications, they could suppress the allergic response, leading to a false negative on the allergy test. Pollen allergy, in particular, is classified as an immediate hypersensitivity reaction, which typically manifests as quick, severe reactions soon after exposure to the allergen.
Treatment of hypersensitivities can be approached using various methods. Mild symptoms are often treated with antihistamines, while severe reactions may require epinephrine. Immunotherapy is a long-term treatment that involves gradually introducing increasing doses of allergens to desensitize the immune system. Autoimmune diseases, distinct from allergies, occur when the immune system mistakenly attacks the body's cells. A history of autoimmune diseases in the family and being female are recognized risk factors for autoimmune conditions.