Keep these guidelines in mind when looking for allergy relief:
Some over-the-counter allergy medications will make you drowsy. They may contain antihistamines, decongestants, or both. Be careful not to take them when you will be driving or working with machinery. Newer antihistamines -- loratadine (Alavert, Claritin), cetirizine (Zyrtec) and fexofenadine (Allegra) -- are available over-the-counter and are less likely to cause you to be sleepy.
Make sure you follow the package instructions. Don't take more or more often than directed. Make sure you know whether or not you can take the medication with your other medications or with medical conditions you may have.
Nonprescription decongestant nasal sprays or drops may make you feel better for a while, but they have a "rebound effect" that can actually increase congestion or stuffiness in your nose. make sure you:
Watch for side effects such as nosebleeds, rapid heartbeat, and agitation.
Use them for only a few days at a time, usually three days of continued use. It's safe to use them again after giving your nose a few days' rest.
Saline sprays or drops can help moisten nasal secretions and help clear the nose and sinuses. They are safe to use continuously.
Nasal corticosteroid sprays are very effective for treating nasal allergies. They may take a few days until you notice an improvement in symptoms.
Nasal antihistamine sprays are also effective and available by prescription. They may also cause sleepiness.