Other methods to reduce exposure to allergens is to get a HEPA vacuum machine in the house, clean the air ducts in the home, and use a good vacuum cleaner. Medical Therapy Antihistamines are the most common medication for allergic rhinitis. Thus, antihistamines prevent sneezing, itching, and some of the congestion experienced by those who suffer from allergic rhinitis. The first non-sedating antihistamine, Seldane, was released in 1985. These drugs are sometimes formulated in combination with an oral decongestant.
Decongestants add to the effect of antihistamines by reducing swelling of the nasal passages.
Steroid nasal sprays can also be prescribed and can be very effective. Steroids reduce swelling by controlling the release of fluids from vessels to surrounding tissues. The effects of the spray take at least a few days to begin while full effect may take weeks to achieve. Nevertheless, steroid nasal spray is the most effective and safest medication currently available. It also relieves nasal symptoms when non-allergic rhinitis is present, that is, when the trigger of nasal congestion is not an allergen.