prick test, but is also more often positive in people that do not have symptoms to that allergen. even if a person has negative skin-prick, intradermal and blood tests for allergies, they may still have allergic rhinitis, from a local allergy in the nose. this is called local allergic rhinitis. specialized testing is necessary to diagnose local allergic rhinitis. classification seasonal allergic rhinitis (hay fever): caused by seasonal peaks in the airborne load of pollens. perennial allergic rhinitis (nonseasonal allergic rhinitis; atopic rhinitis): caused by allergens present throughout the year (e.g., dander). allergic rhinitis may be seasonal, perennial, or episodic. seasonal allergic rhinitis occurs in particular during pollen seasons. it does not usually develop until after 6 years of age. perennial allergic rhinitis occurs throughout the year. this type of allergic rhinitis is commonly seen in younger children. allergic rhinitis may also be classified as mild-intermittent, moderate-severe intermittent, mild-persistent, and moderate-severe persistent. intermittent is when the symptoms occur <4 days per week or <4 consecutive weeks. persistent is when symptoms occur >4 days/week and >4 consecutive weeks. the symptoms are considered mild with normal sleep, no impairment of daily activities, no impairment of work or school, and if symptoms are not troublesome. severe symptoms result in sleep disturbance, impairment of daily activities, and impairment of school or work. local allergic rhinitis local allergic rhinitis is an allergic reaction in the nose to an allergen, without systemic allergies. so skin-prick and blood tests for allergy are negative, but there are ige antibodies produced in the nose that react to a specific allergen. intradermal skin testing may also be negative. the symptoms of local allergic rhinitis are the same as the symptoms of allergic rhinitis, including symptoms in the eyes. just as with allergic rhinitis, people can have either seasonal or perennial local allergic rhinitis. the symptoms of local allergic rhinitis can be mild, moderate, or severe. local allergic rhinitis is associated with conjunctivitis and asthma. in one study, about 25% of people with rhinitis had local allergic rhinitis. in several studies, over 40% of people having been diagnosed with nonallergic rhinitis were found to actually have local allergic rhinitis. steroid nasal sprays and oral antihistamines have been found to be effective for local allergic rhinitis. as of 2014, local allergenic rhinitis had mostly been investigated in europe; in the united states, the nasal provocation testing necessary to diagnose the condition was not widely available.: 617 prevention prevention often focuses on avoiding specific allergens that cause an individual's symptoms. these methods include not having pets, not having carpets or upholstered furniture in the home, and keeping the home dry. specific anti-allergy zippered covers on household items like pillows and mattresses have also proven to be effective in preventing dust mite allergies. studies have shown that growing up on a farm and having many older siblings can decrease an individual's risk for developing allergic rhinitis. studies in young children have shown that there is higher risk of allergic rhinitis in those who have early exposure to foods or formula or heavy exposure to cigarette smoking within the first year of life. treatment the goal of rhinitis treatment is to prevent or reduce the symptoms caused by the inflammation of affected tissues. measures that are effective include avoiding the allergen. intranasal corticosteroids are the preferred medical treatment for persistent symptoms, with other options if this is not effective. second line therapies include antihistamines, decongestants, cromolyn, leukotriene receptor antagonists, and nasal irrigation. antihistamines by mouth are suitable for occasional use with mild intermittent symptoms. mite-proof covers, air filters, and withholding certain foods in childhood do not have evidence supporting their effectiveness. antihistamines antihistamine drugs can be taken orally and nasally to control symptoms such as sneezing, rhinorrhea, itching, and conjunctivitis. it is best to take oral antihistamine medication before exposure, especially for seasonal allergic rhinitis. in the case of nasal antihistamines like azelastine antihistamine nasal spray, relief from symptoms is experienced within 15 minutes allowing for a more immediate 'as-needed' approach to dosage. there is not enough evidence of antihistamine efficacy as an add-on therapy with nasal steroids in the management of intermittent or persistent allergic rhinitis in children, so its adverse effects and additional costs must be considered. ophthalmic antihistamines (such as azelastine in eye drop form and ketotifen) are used for conjunctivitis, while intranasal forms are used mainly for sneezing, rhinorrhea, and nasal pruritus. antihistamine drugs can have undesirable side-effects, the most notable one being drowsiness in the case of oral antihistamine tablets. first-generation antihistamine drugs such as diphenhydramine cause drowsiness, while second- and third-generation antihistamines such as cetirizine and loratadine are less likely to. pseudoephedrine is also indicated for vasomotor rhinitis. it is used only when nasal congestion is present and can be used with antihistamines. in the united states, oral decongestants containing pseudoephedrine must be purchased behind the pharmacy counter in an effort to prevent the manufacturing of methamphetamine. desloratadine/pseudoephedrine can also be used for this condition steroids intranasal corticosteroids are used to control symptoms associated with sneezing, rhinorrhea, itching, and nasal congestion. steroid nasal sprays are effective and safe, and may be effective without oral antihistamines. they take several days to act and so must be taken continually for several weeks, as their therapeutic effect builds up with time. in 2013, a study compared the efficacy of mometasone furoate nasal spray to betamethasone oral tablets for the treatment of people with seasonal allergic rhinitis and found that the two have virtually equivalent effects on nasal symptoms in people. systemic steroids such as prednisone tablets and intramuscular triamcinolone acetonide or glucocorticoid (such as betamethasone) injection are effective at reducing nasal inflammation, but their use is limited by their short duration of effect and the side-effects of prolonged steroid therapy. other other measures that may be used second line include: decongestants, cromolyn, leukotriene receptor antagonists, and nonpharmacologic therapies such as nasal irrigation. topical decongestants may also be helpful in reducing symptoms such as nasal congestion, but should not be used for long periods, as stopping them after protracted use can lead to a rebound nasal congestion called rhinitis medicamentosa. for nocturnal symptoms, intranasal corticosteroids can be combined with nightly oxymetazoline, an adrenergic alpha-agonist, or an antihistamine nasal spray without risk of rhinitis medicamentosa. nasal saline irrigation (a practice where salt water is poured into the nostrils), may have benefits in both adults and children in relieving the symptoms of allergic rhinitis and it is unlikely to be associated with adverse effects. allergen immunotherapy allergen immunotherapy (ait, also termed desensitization) treatment involves administering doses of allergens to accustom the body to substances that are generally harmless (pollen, house dust mites), thereby inducing specific long-term tolerance. allergen immunotherapy is the only treatment that alters the disease mechanism. immunotherapy can be administered orally (as sublingual tablets or sublingual drops), or by injections under the skin (subcutaneous). subcutaneous immunotherapy is the most common form and has the largest body of evidence supporting its effectiveness. alternative medicine there are no forms of complementary or alternative medicine that are evidence-based for allergic rhinitis. therapeutic efficacy of alternative treatments such as acupuncture and homeopathy is not supported by available evidence. while some evidence shows that acupuncture is effective for rhinitis, specifically targeting the sphenopalatine ganglion acupoint, these trials are still limited. overall, the quality of evidence for complementary-alternative medicine is not strong enough to be recommended by the american academy of allergy, asthma and immunology. epidemiology allergic rhinitis is the type of allergy that affects the greatest number of people. in western countries, between 10 and 30 percent of people are affected in a given year. it is most common between the ages of twenty and forty. history the first accurate description is from the 10th century physician rhazes. pollen was identified as the cause in 1859 by charles blackley. in 1906 the mechanism was determined by clemens von pirquet. the link with hay came about due to an early (and incorrect) theory that the symptoms were brought about by the smell of new hay.