Nasal allergy medications fall into three categories of usage.

Preventive:For people who have chronic symptoms of rhinitis, allergic or nonallergic,the most effective approach is to use antihistamines and nasal corticosteroid medications preventively.

Stabilizing:These drugs can often stop a reaction that's already in process before your immune system can release potent chemical mediator of inflammation,such as histamine and leukotrienes,that produce noticeable symptoms.

Relief:Most of the commonly available over the counter oral antihistamines and decongestants fall into this category.Most people use them to relieve the symptoms of rhinitis after symptoms have occurred.

A few basic types of drugs are used to treat nasal allergies,including:antihistamines,decongestants,combination of antihistamine and decongestant product.