This involves periodic injections of small amounts of allergen over a period of three to five years in an effort to make the immune system more resistant to specific allergens and lessen the need for medications. Many people may not realize they have allergies, often attributing their congestion and runny nose to a cold. Left untreated, allergies can cause more serious conditions like sinusitis or ear infections. If seasonal allergies, symptoms occur at the same time every year. If perennial allergies, symptoms are present year-round.
Symptoms develop within one to three days of exposure to the cold virus.
Duration Symptoms last as long as you are exposed to the allergen. Five to seven days.