How does Allergena work? The immune system defends us against disease. When harmful substances are detected, such as pollens, the immune system creates antibodies, which destroy or neutralize allergens (i.e. pollens, dust and/or mold) that cause us to have allergic reactions. However, sometimes even our immune system is not strong enough to defend against these allergens. Allergena is a Homeopathic Sublingual Immunotherapy that reduces the body's negative reaction to allergens. Our homeopathic allergy drops build immunity by exposing your body in micro doses to whatever it is that you are allergic to. This way, the body becomes safely conditioned to tolerate the allergens that previously brought on allergic reactions, and ultimately reduce allergic symptoms. Below are a few definitions to give you a better idea of how Allergena works: Sublingual: Underneath the tongue. Immunotherapy: Treatment to stimulate or restore the ability of the immune (defense) system to fight infection and disease. Allergy shots are another form of Immunotherapy.