Treatment strategies for allergic diseases are based on allergen avoidance, pharmacotherapy and immunotherapy. Allergen avoidance should always be attempted, even if it is rarely complete and needs several days or weeks to be effective. Pharmacotherapy is aimed at reducing symptoms arising from allergen triggers and inflammation. In seasonal allergic diseases, a short treatment course is sufficient to reverse nonspecific hyperreactivity and symptoms. In chronic allergic diseases, however, inflammation is of major importance and symptoms are not always readily controlled. Moreover, the treatment should be prolonged as proposed by Guidelines for the Management of Asthma and Rhinitis (1, 2). Effective and well-tolerated drugs are now available and some may be combined for rhinitis or asthma therapy. In rhinitis, first-line therapy is still based on non-sedating antihistamines and topical corticosteroids. Cromoglycate and other drugs may also be used. For asthma, anti-inflammatory therapy is the first-line treatment. In mild sufferers, cromoglycate, nedocromil or low-dose inhaled steroids can be used. For more severe disease, high doses of inhaled corticosteroids are proposed. Bronchodilators are used as 'rescue' medications, though many patients with severe symptoms need regular bronchodilator therapy. Long-acting beta 2-agonists have been introduced recently, but their exact place in the management of asthma is not yet fully established. Immunotherapy was first introduced in 1911 and was based on decades of physicians' experience, rather than on rational thought. Standardized allergens have improved the efficacy of immunotherapy, but the safety of this treatment needs to be improved.(ABSTRACT TRUNCATED AT 250 WORDS)