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Allergy and Antihistamine Information Frequently Asked Antihistamine Questions When should I start taking an antihistamine?
When should I start taking an antihistamine?
If your allergy is seasonal, then the best idea is to take an antihistamine before the season begins. Allergy medications are better at preventing symptoms before they develop rather than treating those that are already present in the system. For example, nasal corticosteroids like Beconase, Butacort 50, and Flixonase are usually more effective if taken two weeks before the start of the allergy season because it can take a week or two for them to reach their maximum effectiveness. Allergy medications are also more effective if they are taken on a regular schedule during the allergy season. If you have a perennial allergy then you can take antihistamines or nasal corticosteroids all year round for relief.