Full and accurate diagnosis of allergic rhinitis is important as a basis for treatment decisions, as many nasal disorders have similar signs and symptoms. Optimal allergen avoidance is the starting point of treatment, so causative allergens need to be identified. Oral antihistamines are effective in relieving the majority of symptoms of allergic rhinitis and allergic conjunctivitis, but provide only partial relief from nasal congestion. Topical α-adrenergic decongestants help to relieve congestion, but prolonged use leads to rhinitis medicamentosa. Systemic decongestants are less effective than topical agents and their use is limited by systemic and central side-effects. The value of leukotriene antagonists has yet to be fully evaluated. Intranasal ipratropium bromide helps to control watery secretions, and an aerosol may be more effective than an aqueous solution. Topical glucocorticosteroids, such as triamcinolone, are the most potent and effective agents available for treating allergic rhinitis. The available evidence indicates that there is very little systemic absorption. Sodium cromoglycate is effective in allergic rhinitis, though less so than topical steroids, and has the least adverse effects among the antiallergic agents. Immunotherapy can be effective and may be indicated in individuals who cannot avoid the causative allergen. Special considerations apply to the treatment of allergic rhinitis in elderly or pregnant patients. Finally, patients with long-standing allergic conditions should be re-assessed regularly.