Although antihistamines can effectively treat some allergic symptoms, they cannot decrease inflammation and nasal congestion.  The pharmacological approach focuses on decreasing inflammation by stabilizing mast cells and basophils, while decreasing the release of chemical mediators and blocking the effects of histamine, leukotrienes, and prostaglandins.

Currently, the most effective medication available to control sneezing, itching, nasal drainage, and nasal congestion are corticosteroid nasal sprays such as Flonase, Nasacort AQ, Nasonex, Rhinocort, Omnaris, Zetonna, Veramyst, and Patanase.  Corticosteroid nasal sprays reduce allergic symptoms by blocking leukotrienes, prostaglandins, and other chemical mediators to reduce inflammation.  These sprays must be used regularly in order for them to work and it may take one to three weeks to achieve maximum benefit.

Side effects of corticosteroid nasal sprays are generally mild and limited to the nose.  If the spray is used incorrectly, the patient may experience burning, stinging, and irritation of the lining of the nose or nasal septum.  Patients are advised not to point the nozzle of the spray toward the nasal septum as this can injure the septum.  Rather, the nozzle should be pointed slanted back, following the direction of airflow into the nose.

The antihistamine nasal spray Astelin (azelastine), usually takes affect within three hours.  In contrast to most oral antihistamines, it is also effective in reducing nasal congestion.  Dymista (azelastine hydrochloride and fluticasone propionate), another nasal spray, combines corticosteroid with antihistamine has proven more effective than either nasal corticosteroid spray or antihistamine nasal sprays alone.

Cromolyn sodium, which is not an antihistamine, decongestant, or steroid, is widely prescribed because of its ability to prevent the release of chemical mediators from mast cells into the nasal tissue.  For the best results, Cromolyn sodium should be started two weeks before allergy season.  Although Cromolyn is not as effective as corticosteroid nasal sprays, doctors may often prescribe it to children and pregnant woman because of its excellent safety profile and minor side effects. Moreover, Singulair (montelukast), a leukotriene blocker in pill form, can also be used to treat mild asthma and is therefore a good choice for patients with mild allergic rhinitis and asthma.