Allergic rhinitis occurs seasonally or year-round. Diagnosis involves history-taking, examination of the nasal passages and sometimes skin testing. Over 400 million people suffer from allergic rhinitis around the world, which to a large extent remains underdiagnosed and undertreated. In the United States it affects between 10-30% of the adult general population and up to 40% of children, making it the fifth most common chronic disease. Unfortunately the health and economic impact of allergic rhinitis historically has been grossly underestimated and it is only recently that rhinitis has been recognized as a serious issue with epidemic proportions. Direct medical costs in The US increased from $6.1 billion in 2000 to $11.2 billion in 2005, with an estimated productivity decrease of $600 per employee yearly; this cost is greater than diabetes, coronary heart disease and asthma. Indirect losses represent an even heavier burden in societies with emerging economies. In eight countries in the Asia Pacific region, the annual per-patient direct costs ranged from the equivalent of US$ 108 to US$ 1,010.62 Total per-patient costs, including productivity costs, ranged from US$ 184 to US$ 1,189. Thus, the cost of allergic rhinitis is enormous and widely under-appreciated.