Your first line of defense is to avoid the allergens, the substances that you are allergic to. If you find this is not completely effective you will want to talk with your primary care provider. He or she may prescribe antihistamines, decongestants or nasal sprays. Antihistamines Antihistamines stop your body from making histamine. This is a substance produced by your body when you are exposed to an allergen.
Histamine is what causes the allergic symptoms.
Taking the antihistamine 30 minutes before going outside may produce the best results. It is important to note that some antihistamines may cause drowsiness, especially with the over the counter products. Due to the potential drowsiness, care must be taken with driving or operating heavy machinery. Decongestants Decongestants relieve nasal congestion by shrinking the blood vessels in the nose. They do not stop sneezing or itchy eyes.