| According to a latest study conducted in the United States, "Allergies affect around 20% of Americans while asthma affects an estimated 17 million people in the U.S. alone". Allergy or hypersensitivity is a reaction of our immune system in response our body's contact with harmful allergens. Anti-allergy medications are commonly used for preventing and relieving allergy symptoms. There are countless number of both over-the-counter and prescription medications available in the market to reduce annoying allergic reactions. Anti-allergic drugs include cetirizine, chlorpheniramine maleate, decongestants, antihistamines, antiflamatory agents, anti leukotrienes and other combination medicines. These anti allergy medicines can be consumed in form of syrups, tablets, powder and drops. When consumed, these anti allergic drugs support the immune system and improve its overall resistance against allergens. The worldwide market for allergy remedies market continues to grow rapidly with annual sales of US $ 36 billion.